@article{flaschner_experimental_2015,
title = {Experimental reconstruction of the {Berry} curvature in a topological {Bloch} band},
url = {http://arxiv.org/abs/1509.05763},
abstract = {Topological properties lie at the heart of many fascinating phenomena in solid state systems such as quantum Hall systems or Chern insulators. The topology can be captured by the distribution of Berry curvature, which describes the geometry of the eigenstates across the Brillouin zone. Employing fermionic ultracold atoms in a hexagonal optical lattice, we generate topological bands using resonant driving and show a full momentum-resolved measurement of the ensuing Berry curvature. Our results pave the way to explore intriguing phases of matter with interactions in topological band structures.},
urldate = {2015-12-04},
journal = {arXiv:1509.05763 [cond-mat]},
author = {Fl{\"a}schner, N. and Rem, B. S. and Tarnowski, M. and Vogel, D. and L{\"u}hmann, D.-S. and Sengstock, K. and Weitenberg, C.},
month = sep,
year = {2015},
note = {arXiv: 1509.05763},
keywords = {Condensed Matter - Quantum Gases},
file = {arXiv\:1509.05763 PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/88HPRQPD/Fl{\"a}schner et al. - 2015 - Experimental reconstruction of the Berry curvature.pdf:application/pdf;arXiv.org Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/NW45V8S8/1509.html:text/html}
}
@article{fuchs_topological_2010,
title = {Topological {Berry} phase and semiclassical quantization of cyclotron orbits for two dimensional electrons in coupled band models},
volume = {77},
issn = {1434-6028, 1434-6036},
url = {http://link.springer.com/article/10.1140/epjb/e2010-00259-2},
doi = {10.1140/epjb/e2010-00259-2},
abstract = {. The semiclassical quantization of cyclotron orbits for two-dimensional Bloch electrons in a coupled two band model with a particle-hole symmetric spectrum is considered. As concrete examples, we study graphene (both mono and bilayer) and boron nitride. The main focus is on wave effects {\textendash} such as Berry phase and Maslov index {\textendash} occurring at order ?{\textbackslash}hbar in the semiclassical quantization and producing non-trivial shifts in the resulting Landau levels. Specifically, we show that the index shift appearing in the Landau levels is related to a topological part of the Berry phase {\textendash} which is basically a winding number of the direction of the pseudo-spin 1/2 associated to the coupled bands {\textendash} acquired by an electron during a cyclotron orbit and not to the complete Berry phase, as commonly stated. As a consequence, the Landau levels of a coupled band insulator are shifted as compared to a usual band insulator. We also study in detail the Berry curvature in the whole Brillouin zone on a specific example (boron nitride) and show that its computation requires care in defining the {\textquotedblleft}k-dependent Hamiltonian{\textquotedblright} H(k), where k is the Bloch wavevector.},
language = {en},
number = {3},
urldate = {2015-12-04},
journal = {Eur. Phys. J. B},
author = {Fuchs, J. N. and Pi{\'e}chon, F. and Goerbig, M. O. and Montambaux, G.},
month = sep,
year = {2010},
keywords = {Condensed Matter Physics, Fluid- and Aerodynamics, Physics, general, Solid State Physics, Statistical Physics, Dynamical Systems and Complexity},
pages = {351--362},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/BEWGNDG4/Fuchs et al. - 2010 - Topological Berry phase and semiclassical quantiza.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/UWD3TSUV/10.html:text/html}
}
@article{fulga_scattering_2015,
title = {Scattering theory of {Floquet} topological insulators},
url = {http://arxiv.org/abs/1508.02726},
abstract = {Similar to static systems, periodically driven systems can host a variety of topologically non-trivial phases. Unlike the case of static Hamiltonians, the topological indices of bulk Floquet bands may fail to describe the presence and robustness of edge states, prompting the search for new invariants. We develop a unified description of topological phases and their invariants in driven systems, by using scattering theory. We show that scattering matrix invariants correctly describe the topological phase, even when all bulk Floquet bands are trivial. Additionally, we use scattering theory to introduce and analyze new periodically driven phases, such as weak topological Floquet insulators, for which invariants were previously unknown. We highlight some of their similarities with static systems, including robustness to disorder, as well as some of the features unique to driven systems, showing that the weak phase may be destroyed by breaking translational symmetry not in space, but in time.},
urldate = {2015-08-17},
journal = {arXiv:1508.02726 [cond-mat]},
author = {Fulga, I. C. and Maksymenko, M.},
month = aug,
year = {2015},
note = {arXiv: 1508.02726},
keywords = {Condensed Matter - Mesoscale and Nanoscale Physics},
annote = {Comment: 10 pages, 8 figures},
file = {arXiv\:1508.02726 PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/DXQEGQJW/Fulga und Maksymenko - 2015 - Scattering theory of Floquet topological insulator.pdf:application/pdf;arXiv.org Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/KBE83P35/1508.html:text/html}
}
@article{haldane_model_1988,
title = {Model for a {Quantum} {Hall} {Effect} without {Landau} {Levels}: {Condensed}-{Matter} {Realization} of the "{Parity} {Anomaly}"},
volume = {61},
shorttitle = {Model for a {Quantum} {Hall} {Effect} without {Landau} {Levels}},
url = {http://link.aps.org/doi/10.1103/PhysRevLett.61.2015},
doi = {10.1103/PhysRevLett.61.2015},
abstract = {A two-dimensional condensed-matter lattice model is presented which exhibits a nonzero quantization of the Hall conductance $\sigma$xy in the absence of an external magnetic field. Massless fermions without spectral doubling occur at critical values of the model parameters, and exhibit the so-called "parity anomaly" of (2+1)-dimensional field theories.},
number = {18},
urldate = {2016-01-12},
journal = {Phys. Rev. Lett.},
author = {Haldane, F. D. M.},
month = oct,
year = {1988},
pages = {2015--2018},
file = {APS Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/X39FEVE8/PhysRevLett.61.html:text/html;Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/PTBEJQKG/Haldane - 1988 - Model for a Quantum Hall Effect without Landau Lev.pdf:application/pdf}
}
@article{hasan_textitcolloquium_2010,
title = {{\textbackslash}textit\{{Colloquium}\} : {Topological} insulators},
volume = {82},
shorttitle = {{\textbackslash}textit\{{Colloquium}\}},
url = {http://link.aps.org/doi/10.1103/RevModPhys.82.3045},
doi = {10.1103/RevModPhys.82.3045},
abstract = {Topological insulators are electronic materials that have a bulk band gap like an ordinary insulator but have protected conducting states on their edge or surface. These states are possible due to the combination of spin-orbit interactions and time-reversal symmetry. The two-dimensional (2D) topological insulator is a quantum spin Hall insulator, which is a close cousin of the integer quantum Hall state. A three-dimensional (3D) topological insulator supports novel spin-polarized 2D Dirac fermions on its surface. In this Colloquium the theoretical foundation for topological insulators and superconductors is reviewed and recent experiments are described in which the signatures of topological insulators have been observed. Transport experiments on HgTe/CdTe quantum wells are described that demonstrate the existence of the edge states predicted for the quantum spin Hall insulator. Experiments on Bi1-xSbx, Bi2Se3, Bi2Te3, and Sb2Te3 are then discussed that establish these materials as 3D topological insulators and directly probe the topology of their surface states. Exotic states are described that can occur at the surface of a 3D topological insulator due to an induced energy gap. A magnetic gap leads to a novel quantum Hall state that gives rise to a topological magnetoelectric effect. A superconducting energy gap leads to a state that supports Majorana fermions and may provide a new venue for realizing proposals for topological quantum computation. Prospects for observing these exotic states are also discussed, as well as other potential device applications of topological insulators.},
number = {4},
urldate = {2015-12-04},
journal = {Rev. Mod. Phys.},
author = {Hasan, M. Z. and Kane, C. L.},
month = nov,
year = {2010},
pages = {3045--3067},
file = {APS Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/MIH3Q27I/RevModPhys.82.html:text/html;Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/NQP6SGQP/Hasan und Kane - 2010 - textit Colloquium Topological insulators.pdf:application/pdf}
}
@article{hone_time-dependent_1997,
title = {Time-dependent {Floquet} theory and absence of an adiabatic limit},
volume = {56},
url = {http://link.aps.org/doi/10.1103/PhysRevA.56.4045},
doi = {10.1103/PhysRevA.56.4045},
abstract = {Quantum systems subject to time periodic fields of finite amplitude $\lambda$ have conventionally been handled either by low-order perturbation theory, for $\lambda$ not too large, or by exact diagonalization within a finite basis of N states. An adiabatic limit, as $\lambda$ is switched on arbitrarily slowly, has been assumed. But the validity of these procedures seems questionable in view of the fact that, as N{\textrightarrow}$\infty$, the quasienergy spectrum becomes dense, and numerical calculations show an increasing number of weakly avoided crossings (related in perturbation theory to high-order resonances). This paper deals with the highly nontrivial behavior of the solutions in this limit. The Floquet states, and the associated quasienergies, become highly irregular functions of the amplitude $\lambda$. The mathematical radii of convergence of perturbation theory in $\lambda$ approach zero. There is no adiabatic limit of the wave functions when $\lambda$ is turned on arbitrarily slowly. However, the quasienergy becomes independent of $\lambda$(t) in this limit. We introduce a modification of the adiabatic theorem. We explain why, in spite of the pervasive pathologies of the Floquet states in the limit N{\textrightarrow}$\infty$, the conventional approaches are appropriate in almost all physically interesting situations.},
number = {5},
urldate = {2015-12-04},
journal = {Phys. Rev. A},
author = {Hone, Daniel W. and Ketzmerick, Roland and Kohn, Walter},
month = nov,
year = {1997},
pages = {4045--4054},
file = {APS Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/AMSW76S3/PhysRevA.56.html:text/html;Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/N7F55V5Q/Hone et al. - 1997 - Time-dependent Floquet theory and absence of an ad.pdf:application/pdf}
}
@article{jotzu_experimental_2014,
title = {Experimental realization of the topological {Haldane} model with ultracold fermions},
volume = {515},
copyright = {{\textcopyright} 2014 Nature Publishing Group, a division of Macmillan Publishers Limited. All Rights Reserved.},
issn = {0028-0836},
url = {http://www.nature.com/nature/journal/v515/n7526/full/nature13915.html},
doi = {10.1038/nature13915},
abstract = {The Haldane model on a honeycomb lattice is a paradigmatic example of a Hamiltonian featuring topologically distinct phases of matter. It describes a mechanism through which a quantum Hall effect can appear as an intrinsic property of a band structure, rather than being caused by an external magnetic field. Although physical implementation has been considered unlikely, the Haldane model has provided the conceptual basis for theoretical and experimental research exploring topological insulators and superconductors. Here we report the experimental realization of the Haldane model and the characterization of its topological band structure, using ultracold fermionic atoms in a periodically modulated optical honeycomb lattice. The Haldane model is based on breaking both time-reversal symmetry and inversion symmetry. To break time-reversal symmetry, we introduce complex next-nearest-neighbour tunnelling terms, which we induce through circular modulation of the lattice position. To break inversion symmetry, we create an energy offset between neighbouring sites. Breaking either of these symmetries opens a gap in the band structure, which we probe using momentum-resolved interband transitions. We explore the resulting Berry curvatures, which characterize the topology of the lowest band, by applying a constant force to the atoms and find orthogonal drifts analogous to a Hall current. The competition between the two broken symmetries gives rise to a transition between topologically distinct regimes. By identifying the vanishing gap at a single Dirac point, we map out this transition line experimentally and quantitatively compare it to calculations using Floquet theory without free parameters. We verify that our approach, which allows us to tune the topological properties dynamically, is suitable even for interacting fermionic systems. Furthermore, we propose a direct extension to realize spin-dependent topological Hamiltonians.},
language = {en},
number = {7526},
urldate = {2015-12-04},
journal = {Nature},
author = {Jotzu, Gregor and Messer, Michael and Desbuquois, R{\'e}mi and Lebrat, Martin and Uehlinger, Thomas and Greif, Daniel and Esslinger, Tilman},
month = nov,
year = {2014},
keywords = {Quantum mechanics, Ultracold gases},
pages = {237--240},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/72CBR8RP/Jotzu et al. - 2014 - Experimental realization of the topological Haldan.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/X7UGPT6H/nature13915.html:text/html}
}
@article{kitagawa_transport_2011,
title = {Transport properties of nonequilibrium systems under the application of light: {Photoinduced} quantum {Hall} insulators without {Landau} levels},
volume = {84},
shorttitle = {Transport properties of nonequilibrium systems under the application of light},
url = {http://link.aps.org/doi/10.1103/PhysRevB.84.235108},
doi = {10.1103/PhysRevB.84.235108},
abstract = {In this paper, we study transport properties of nonequilibrium systems under the application of light in many-terminal measurements, using the Floquet picture. We propose and demonstrate that the quantum transport properties can be controlled in materials such as graphene and topological insulators, via the application of light. Remarkably, under the application of off-resonant light, topological transport properties can be induced; these systems exhibit quantum Hall effects in the absence of a magnetic field with a near quantization of the Hall conductance, realizing so-called quantum Hall systems without Landau levels first proposed by Haldane.},
number = {23},
urldate = {2016-01-12},
journal = {Phys. Rev. B},
author = {Kitagawa, Takuya and Oka, Takashi and Brataas, Arne and Fu, Liang and Demler, Eugene},
month = dec,
year = {2011},
pages = {235108},
file = {APS Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/T6BGJWE4/PhysRevB.84.html:text/html;Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/ENV884CH/Kitagawa et al. - 2011 - Transport properties of nonequilibrium systems und.pdf:application/pdf}
}
@article{lindner_floquet_2011,
title = {Floquet topological insulator in semiconductor quantum wells},
volume = {7},
copyright = {{\textcopyright} 2011 Nature Publishing Group},
issn = {1745-2473},
url = {http://www.nature.com/nphys/journal/v7/n6/abs/nphys1926.html},
doi = {10.1038/nphys1926},
abstract = {Topological phases of matter have captured our imagination over the past few years, with tantalizing properties such as robust edge modes and exotic non-Abelian excitations, and potential applications ranging from semiconductor spintronics to topological quantum computation. Despite recent advancements in the field, our ability to control topological transitions remains limited, and usually requires changing material or structural properties. We show, using Floquet theory, that a topological state can be induced in a semiconductor quantum well, initially in the trivial phase. This can be achieved by irradiation with microwave frequencies, without changing the well structure, closing the gap and crossing the phase transition. We show that the quasi-energy spectrum exhibits a single pair of helical edge states. We discuss the necessary experimental parameters for our proposal. This proposal provides an example and a proof of principle of a new non-equilibrium topological state, the Floquet topological insulator, introduced in this paper.
View full text},
language = {en},
number = {6},
urldate = {2016-01-12},
journal = {Nat Phys},
author = {Lindner, Netanel H. and Refael, Gil and Galitski, Victor},
month = jun,
year = {2011},
pages = {490--495},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/3U3GFQAX/Lindner et al. - 2011 - Floquet topological insulator in semiconductor qua.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/T7MAP4QS/nphys1926.html:text/html}
}
@article{mahmood_selective_2016,
title = {Selective scattering between {Floquet}-{Bloch} and {Volkov} states in a topological insulator},
volume = {advance online publication},
copyright = {{\textcopyright} 2016 Nature Publishing Group},
issn = {1745-2473},
url = {http://www.nature.com/nphys/journal/vaop/ncurrent/full/nphys3609.html},
doi = {10.1038/nphys3609},
abstract = {The coherent optical manipulation of solids is emerging as a promising way to engineer novel quantum states of matter. The strong time-periodic potential of intense laser light can be used to generate hybrid photon{\textendash}electron states. Interaction of light with Bloch states leads to Floquet{\textendash}Bloch states, which are essential in realizing new photo-induced quantum phases. Similarly, dressing of free-electron states near the surface of a solid generates Volkov states, which are used to study nonlinear optics in atoms and semiconductors. The interaction of these two dynamic states with each other remains an open experimental problem. Here we use time- and angle-resolved photoemission spectroscopy (Tr-ARPES) to selectively study the transition between these two states on the surface of the topological insulator Bi2Se3. We find that the coupling between the two strongly depends on the electron momentum, providing a route to enhance or inhibit it. Moreover, by controlling the light polarization we can negate Volkov states to generate pure Floquet{\textendash}Bloch states. This work establishes a systematic path for the coherent manipulation of solids via light{\textendash}matter interaction.},
language = {en},
urldate = {2016-01-06},
journal = {Nat Phys},
author = {Mahmood, Fahad and Chan, Ching-Kit and Alpichshev, Zhanybek and Gardner, Dillon and Lee, Young and Lee, Patrick A. and Gedik, Nuh},
month = jan,
year = {2016},
keywords = {Electronic properties and materials, Single photons and quantum effects, Topological insulators},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/GVUF2IXP/Mahmood et al. - 2016 - Selective scattering between Floquet-Bloch and Vol.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/M5EI5BXB/nphys3609.html:text/html}
}
@article{oka_photovoltaic_2009,
title = {Photovoltaic {Hall} effect in graphene},
volume = {79},
url = {http://link.aps.org/doi/10.1103/PhysRevB.79.081406},
doi = {10.1103/PhysRevB.79.081406},
abstract = {Response of electronic systems in intense lights (ac electric fields) to dc source-drain fields is formulated with the Floquet method. We have then applied the formalism to graphene, for which we show that a nonlinear effect of a circularly polarized light can open a gap in the Dirac cone, which is predicted to lead to a photoinduced dc Hall current. This is numerically confirmed for a graphene ribbon attached to electrodes with the Keldysh Green{\textquoteright}s function.},
number = {8},
urldate = {2016-01-12},
journal = {Phys. Rev. B},
author = {Oka, Takashi and Aoki, Hideo},
month = feb,
year = {2009},
pages = {081406},
file = {APS Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/8C8NU9PU/PhysRevB.79.html:text/html;Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/958N9N7V/Oka und Aoki - 2009 - Photovoltaic Hall effect in graphene.pdf:application/pdf}
}
@article{qi_topological_2011,
title = {Topological insulators and superconductors},
volume = {83},
url = {http://link.aps.org/doi/10.1103/RevModPhys.83.1057},
doi = {10.1103/RevModPhys.83.1057},
abstract = {Topological insulators are new states of quantum matter which cannot be adiabatically connected to conventional insulators and semiconductors. They are characterized by a full insulating gap in the bulk and gapless edge or surface states which are protected by time-reversal symmetry. These topological materials have been theoretically predicted and experimentally observed in a variety of systems, including HgTe quantum wells, BiSb alloys, and Bi2Te3 and Bi2Se3 crystals. Theoretical models, materials properties, and experimental results on two-dimensional and three-dimensional topological insulators are reviewed, and both the topological band theory and the topological field theory are discussed. Topological superconductors have a full pairing gap in the bulk and gapless surface states consisting of Majorana fermions. The theory of topological superconductors is reviewed, in close analogy to the theory of topological insulators.},
number = {4},
urldate = {2015-09-02},
journal = {Rev. Mod. Phys.},
author = {Qi, Xiao-Liang and Zhang, Shou-Cheng},
year = {2011},
pages = {1057--1110},
file = {APS Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/36TS7SAP/RevModPhys.83.html:text/html;Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/FGFVJFAV/Qi und Zhang - 2011 - Topological insulators and superconductors.pdf:application/pdf}
}
@article{sentef_theory_2015,
title = {Theory of {Floquet} band formation and local pseudospin textures in pump-probe photoemission of graphene},
volume = {6},
copyright = {{\textcopyright} 2015 Nature Publishing Group, a division of Macmillan Publishers Limited. All Rights Reserved.},
url = {http://www.nature.com/ncomms/2015/150511/ncomms8047/abs/ncomms8047.html},
doi = {10.1038/ncomms8047},
abstract = {Ultrafast materials science promises optical control of physical properties of solids. Continuous-wave circularly polarized laser driving was predicted to induce a light-matter coupled state with an energy gap and a quantum Hall effect, coined Floquet topological insulator. Whereas the envisioned Floquet topological insulator requires high-frequency pumping to obtain well-separated Floquet bands, a follow-up question regards the creation of Floquet-like states in graphene with realistic low-frequency laser pulses. Here we predict that short optical pulses attainable in experiments can lead to local spectral gaps and novel pseudospin textures in graphene. Pump-probe photoemission spectroscopy can track these states by measuring sizeable energy gaps and Floquet band formation on femtosecond time scales. Analysing band crossings and pseudospin textures near the Dirac points, we identify new states with optically induced nontrivial changes of sublattice mixing that leads to Berry curvature corrections of electrical transport and magnetization.
View full text},
language = {en},
urldate = {2015-12-04},
journal = {Nat Commun},
author = {Sentef, M. A. and Claassen, M. and Kemper, A. F. and Moritz, B. and Oka, T. and Freericks, J. K. and Devereaux, T. P.},
month = may,
year = {2015},
keywords = {Condensed matter, Physical sciences, Theoretical physics},
pages = {7047},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/2D44QGVN/Sentef et al. - 2015 - Theory of Floquet band formation and local pseudos.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/SJ7JVWX3/ncomms8047.html:text/html}
}
@article{shekhar_extremely_2015,
title = {Extremely large magnetoresistance and ultrahigh mobility in the topological {Weyl} semimetal candidate {NbP}},
volume = {11},
copyright = {{\textcopyright} 2014 Nature Publishing Group},
issn = {1745-2473},
url = {http://www.nature.com/nphys/journal/v11/n8/full/nphys3372.html},
doi = {10.1038/nphys3372},
abstract = {Recent experiments have revealed spectacular transport properties in semimetals, such as the large, non-saturating magnetoresistance exhibited by WTe2 (ref. 1). Topological semimetals with massless relativistic electrons have also been predicted as three-dimensional analogues of graphene. These systems are known as Weyl semimetals, and are predicted to have a range of exotic transport properties and surface states, distinct from those of topological insulators. Here we examine the magneto-transport properties of NbP, a material the band structure of which has been predicted to combine the hallmarks of a Weyl semimetal with those of a normal semimetal. We observe an extremely large magnetoresistance of 850,000\% at 1.85 K (250\% at room temperature) in a magnetic field of up to 9 T, without any signs of saturation, and an ultrahigh carrier mobility of 5 {\texttimes} 106 cm2 V-1 s-1 that accompanied by strong Shubnikov{\textendash}de Haas (SdH) oscillations. NbP therefore presents a unique example of a material combining topological and conventional electronic phases, with intriguing physical properties resulting from their interplay.},
language = {en},
number = {8},
urldate = {2016-03-07},
journal = {Nat Phys},
author = {Shekhar, Chandra and Nayak, Ajaya K. and Sun, Yan and Schmidt, Marcus and Nicklas, Michael and Leermakers, Inge and Zeitler, Uli and Skourski, Yurii and Wosnitza, Jochen and Liu, Zhongkai and Chen, Yulin and Schnelle, Walter and Borrmann, Horst and Grin, Yuri and Felser, Claudia and Yan, Binghai},
month = aug,
year = {2015},
keywords = {Topological insulators},
pages = {645--649},
file = {Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/UWBH546K/nphys3372.html:text/html}
}
@article{sie_valley-selective_2014,
title = {Valley-selective optical {Stark} effect in monolayer {WS}2},
volume = {14},
issn = {1476-1122, 1476-4660},
url = {http://arxiv.org/abs/1407.1825},
doi = {10.1038/nmat4156},
abstract = {Breaking space-time symmetries in two-dimensional crystals (2D) can dramatically influence their macroscopic electronic properties. Monolayer transition-metal dichalcogenides (TMDs) are prime examples where the intrinsically broken crystal inversion symmetry permits the generation of valley-selective electron populations, even though the two valleys are energetically degenerate, locked by time-reversal symmetry. Lifting the valley degeneracy in these materials is of great interest because it would allow for valley-specific band engineering and offer additional control in valleytronic applications. While applying a magnetic field should in principle accomplish this task, experiments to date have observed no valley-selective energy level shifts in fields accessible in the laboratory. Here we show the first direct evidence of lifted valley degeneracy in the monolayer TMD WS2. By applying intense circularly polarized light, which breaks time-reversal symmetry, we demonstrate that the exciton level in each valley can be selectively tuned by as much as 18 meV via the optical Stark effect. These results offer a novel way to control valley degree of freedom, and may provide a means to realize new valley-selective Floquet topological phases in 2D TMDs.},
number = {3},
urldate = {2015-05-20},
journal = {Nature Materials},
author = {Sie, Edbert J. and McIver, James W. and Lee, Yi-Hsien and Fu, Liang and Kong, Jing and Gedik, Nuh},
month = dec,
year = {2014},
note = {arXiv: 1407.1825},
keywords = {Condensed Matter - Materials Science, Condensed Matter - Mesoscale and Nanoscale Physics},
pages = {290--294},
file = {arXiv\:1407.1825 PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/AMPCVM4F/Sie et al. - 2014 - Valley-selective optical Stark effect in monolayer.pdf:application/pdf;arXiv.org Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/5JI8ETPG/1407.html:text/html}
}
@article{wadley_electrical_2016,
title = {Electrical switching of an antiferromagnet},
copyright = {Copyright {\textcopyright} 2016, American Association for the Advancement of Science},
issn = {0036-8075, 1095-9203},
url = {http://science.sciencemag.org/content/early/2016/01/13/science.aab1031},
doi = {10.1126/science.aab1031},
abstract = {Antiferromagnets are hard to control by external magnetic fields because of the alternating directions of magnetic moments on individual atoms and the resulting zero net magnetization. However, relativistic quantum mechanics allows for generating current-induced internal fields whose sign alternates with the periodicity of the antiferromagnetic lattice. Using these fields, which couple strongly to the antiferromagnetic order, we demonstrate room-temperature electrical switching between stable configurations in antiferromagnetic CuMnAs thin film devices by applied current with magnitudes of order 106 Acm-2. Electrical writing is combined in our solid-state memory with electrical readout and the stored magnetic state is insensitive to and produces no external magnetic field perturbations, which illustrates the unique merits of antiferromagnets for spintronics.},
language = {en},
urldate = {2016-02-10},
journal = {Science},
author = {Wadley, P. and Howells, B. and {\v Z}elezn{\'y}, J. and Andrews, C. and Hills, V. and Campion, R. P. and Nov{\'a}k, V. and Olejn{\'i}k, K. and Maccherozzi, F. and Dhesi, S. S. and Martin, S. Y. and Wagner, T. and Wunderlich, J. and Freimuth, F. and Mokrousov, Y. and Kune{\v s}, J. and Chauhan, J. S. and Grzybowski, M. J. and Rushforth, A. W. and Edmonds, K. W. and Gallagher, B. L. and Jungwirth, T.},
month = jan,
year = {2016},
pmid = {26841431},
pages = {aab1031},
file = {Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/7RSHXCKS/science.html:text/html}
}
@article{wang_universal_2016,
title = {Universal anyons at the irradiated surface of topological insulator},
volume = {6},
issn = {2045-2322},
url = {http://www.nature.com/articles/srep20075},
doi = {10.1038/srep20075},
urldate = {2016-02-25},
journal = {Scientific Reports},
author = {Wang, Rui and Chen, Wei and Wang, Baigeng and Xing, D. Y.},
month = feb,
year = {2016},
pages = {20075}
}
@article{wang_observation_2013,
title = {Observation of {Floquet}-{Bloch} {States} on the {Surface} of a {Topological} {Insulator}},
volume = {342},
issn = {0036-8075, 1095-9203},
url = {http://www.sciencemag.org/content/342/6157/453},
doi = {10.1126/science.1239834},
abstract = {The unique electronic properties of the surface electrons in a topological insulator are protected by time-reversal symmetry. Circularly polarized light naturally breaks time-reversal symmetry, which may lead to an exotic surface quantum Hall state. Using time- and angle-resolved photoemission spectroscopy, we show that an intense ultrashort midinfrared pulse with energy below the bulk band gap hybridizes with the surface Dirac fermions of a topological insulator to form Floquet-Bloch bands. These photon-dressed surface bands exhibit polarization-dependent band gaps at avoided crossings. Circularly polarized photons induce an additional gap at the Dirac point, which is a signature of broken time-reversal symmetry on the surface. These observations establish the Floquet-Bloch bands in solids and pave the way for optical manipulation of topological quantum states of matter.
Topological Replicas
When a periodic perturbation couples strongly to electrons in a solid, replicas of the original electronic levels are predicted to develop at certain energies{\textemdash}the so-called Floquet-Bloch states. Such conditions can be achieved by shining light on a solid, but the effect is challenging to observe. Wang et al. (p. 453) used time- and angle-resolved photoemission spectroscopy to photoexcite Bi2Se3 and observe its dispersion at various delay times. The replicas were seen at expected energy shifts, along with the gaps predicted to occur at the new energy-level crossings caused by the appearance of the replicas. Because Bi2Se3 is a topological insulator, the breaking of the time-reversal symmetry caused by circularly polarized light resulted in the appearance of an energy gap at the Dirac point, indicating an interesting route toward manipulating electronic states in such materials.},
language = {en},
number = {6157},
urldate = {2016-01-12},
journal = {Science},
author = {Wang, Y. H. and Steinberg, H. and Jarillo-Herrero, P. and Gedik, N.},
month = oct,
year = {2013},
pmid = {24159040},
pages = {453--457},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/NABQCZPB/Wang et al. - 2013 - Observation of Floquet-Bloch States on the Surface.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/AAE7QCSA/453.html:text/html}
}
@article{wang_dirac_2012,
title = {Dirac semimetal and topological phase transitions in \$\{{A}\}\_\{3\}\${Bi} (\${A}={\textbackslash}text\{{Na}\}\$, {K}, {Rb})},
volume = {85},
url = {http://link.aps.org/doi/10.1103/PhysRevB.85.195320},
doi = {10.1103/PhysRevB.85.195320},
abstract = {Three-dimensional (3D) Dirac point, where two Weyl points overlap in momentum space, is usually unstable and hard to realize. Here we show, based on the first-principles calculations and effective model analysis, that crystalline A3Bi (A=Na, K, Rb) are Dirac semimetals with bulk 3D Dirac points protected by crystal symmetry. They possess nontrivial Fermi arcs on the surfaces and can be driven into various topologically distinct phases by explicit breaking of symmetries. Giant diamagnetism, linear quantum magnetoresistance, and quantum spin Hall effect will be expected for such compounds.},
number = {19},
urldate = {2015-12-04},
journal = {Phys. Rev. B},
author = {Wang, Zhijun and Sun, Yan and Chen, Xing-Qiu and Franchini, Cesare and Xu, Gang and Weng, Hongming and Dai, Xi and Fang, Zhong},
month = may,
year = {2012},
pages = {195320},
file = {APS Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/G2HKGZ78/PhysRevB.85.html:text/html;Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/PS3TSAWS/Wang et al. - 2012 - Dirac semimetal and topological phase transitions .pdf:application/pdf}
}
@article{xiong_evidence_2015,
title = {Evidence for the chiral anomaly in the {Dirac} semimetal {Na}3Bi},
copyright = {Copyright {\textcopyright} 2015, American Association for the Advancement of Science},
issn = {0036-8075, 1095-9203},
url = {http://science.sciencemag.org/content/early/2015/09/02/science.aac6089},
doi = {10.1126/science.aac6089},
abstract = {In a Dirac semimetal, each Dirac node is resolved into two Weyl nodes with opposite {\textquotedblleft}handedness{\textquotedblright} or chirality. The two chiral populations do not mix. However, in parallel electric and magnetic fields (E{\textbar}{\textbar}B), charge is predicted to flow between the Weyl nodes leading to negative magnetoresistance. This {\textquotedblleft}axial{\textquotedblright} current is the chiral (Adler-Bell-Jackiw) anomaly investigated in quantum field theory. We report the observation of a large, negative longitudinal magnetoresistance in the Dirac semimetal Na3Bi. The negative MR is acutely sensitive to deviations of the direction of B from E, and incompatible with conventional transport. By rotating E (as well as B), we show that it is consistent with the prediction of the chiral anomaly.},
language = {en},
urldate = {2016-02-10},
journal = {Science},
author = {Xiong, Jun and Kushwaha, Satya K. and Liang, Tian and Krizan, Jason W. and Hirschberger, Max and Wang, Wudi and Cava, R. J. and Ong, N. P.},
month = sep,
year = {2015},
pmid = {26338798},
pages = {aac6089},
file = {Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/XZUTJHF5/science.html:text/html}
}
@article{zou_floquet_2016,
title = {Floquet {Weyl} fermions in a circularly-polarised-light-irradiated three-dimensional stacked graphene systems},
url = {http://arxiv.org/abs/1601.04497},
abstract = {Using Floquet theory, we illustrate that Floquet Weyl fermions can be created in circularly-polarised-light-irradiated three-dimensional stacked graphene systems. One or two semi-Dirac points can be formed due to overlapping of Floquet sub-bands. Each pair of Weyl points have a two-component semi-Dirac point parent, instead of a four-component Dirac point parent. Decreasing the light frequency will make the Weyl points move in the momentum space, and the Weyl points can approach to the Dirac points when the frequency becomes very small. The frequency-amplitude phase diagram is worked out. It is shown that there exist Fermi arcs in the surface Brillouin zones in circularly-polarised-light-irradiated semi-infinitely-stacked and finitely-multilayered graphene systems. The Floquet Weyl points emerging due to the overlap of Floquet sub-bands provide a new platform to study Weyl fermions.},
urldate = {2016-01-25},
journal = {arXiv:1601.04497 [cond-mat]},
author = {Zou, Jin-Yu and Liu, Bang-Gui},
month = jan,
year = {2016},
note = {arXiv: 1601.04497},
keywords = {Condensed Matter - Mesoscale and Nanoscale Physics},
annote = {Comment: 7 pages, 4 figures},
file = {arXiv\:1601.04497 PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/CFF8B3T7/Zou und Liu - 2016 - Floquet Weyl fermions in a circularly-polarised-li.pdf:application/pdf;arXiv.org Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/GAWVRTTD/1601.html:text/html}
}
@article{liu_evolution_2016,
title = {Evolution of the {Fermi} surface of {Weyl} semimetals in the transition metal pnictide family},
volume = {15},
copyright = {{\textcopyright} 2015 Nature Publishing Group},
issn = {1476-1122},
url = {http://www.nature.com/nmat/journal/v15/n1/full/nmat4457.html},
doi = {10.1038/nmat4457},
abstract = {Topological Weyl semimetals (TWSs) represent a novel state of topological quantum matter which not only possesses Weyl fermions (massless chiral particles that can be viewed as magnetic monopoles in momentum space) in the bulk and unique Fermi arcs generated by topological surface states, but also exhibits appealing physical properties such as extremely large magnetoresistance and ultra-high carrier mobility. Here, by performing angle-resolved photoemission spectroscopy (ARPES) on NbP and TaP, we directly observed their band structures with characteristic Fermi arcs of TWSs. Furthermore, by systematically investigating NbP, TaP and TaAs from the same transition metal monopnictide family, we discovered their Fermiology evolution with spin{\textendash}orbit coupling (SOC) strength. Our experimental findings not only reveal the mechanism to realize and fine-tune the electronic structures of TWSs, but also provide a rich material base for exploring many exotic physical phenomena (for example, chiral magnetic effects, negative magnetoresistance, and the quantum anomalous Hall effect) and novel future applications.},
language = {en},
number = {1},
urldate = {2016-03-08},
journal = {Nat Mater},
author = {Liu, Z. K. and Yang, L. X. and Sun, Y. and Zhang, T. and Peng, H. and Yang, H. F. and Chen, C. and Zhang, Y. and Guo, Y. F. and Prabhakaran, D. and Schmidt, M. and Hussain, Z. and Mo, S.-K. and Felser, C. and Yan, B. and Chen, Y. L.},
month = jan,
year = {2016},
keywords = {Electronic properties and materials, Topological insulators},
pages = {27--31},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/DGID5567/Liu et al. - 2016 - Evolution of the Fermi surface of Weyl semimetals .pdf:application/pdf;nmat4457-s1.pdf:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/GWJFXQ9W/nmat4457-s1.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/MAUTQCAP/nmat4457.html:text/html}
}
@article{weng_weyl_2015,
title = {Weyl {Semimetal} {Phase} in {Noncentrosymmetric} {Transition}-{Metal} {Monophosphides}},
volume = {5},
url = {http://link.aps.org/doi/10.1103/PhysRevX.5.011029},
doi = {10.1103/PhysRevX.5.011029},
abstract = {Based on first-principle calculations, we show that a family of nonmagnetic materials including TaAs, TaP, NbAs, and NbP are Weyl semimetals (WSM) without inversion centers. We find twelve pairs of Weyl points in the whole Brillouin zone (BZ) for each of them. In the absence of spin-orbit coupling (SOC), band inversions in mirror-invariant planes lead to gapless nodal rings in the energy-momentum dispersion. The strong SOC in these materials then opens full gaps in the mirror planes, generating nonzero mirror Chern numbers and Weyl points off the mirror planes. The resulting surface-state Fermi arc structures on both (001) and (100) surfaces are also obtained, and they show interesting shapes, pointing to fascinating playgrounds for future experimental studies.},
number = {1},
urldate = {2016-03-08},
journal = {Phys. Rev. X},
author = {Weng, Hongming and Fang, Chen and Fang, Zhong and Bernevig, B. Andrei and Dai, Xi},
month = mar,
year = {2015},
pages = {011029},
file = {APS Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/JSPITIDP/PhysRevX.5.html:text/html;Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/8ZIU94PQ/Weng et al. - 2015 - Weyl Semimetal Phase in Noncentrosymmetric Transit.pdf:application/pdf}
}
@article{tafti_resistivity_2016,
title = {Resistivity plateau and extreme magnetoresistance in {LaSb}},
volume = {12},
copyright = {{\textcopyright} 2015 Nature Publishing Group},
issn = {1745-2473},
url = {http://www.nature.com/nphys/journal/v12/n3/full/nphys3581.html},
doi = {10.1038/nphys3581},
abstract = {Time reversal symmetry (TRS) protects the metallic surface modes of topological insulators (TIs). The transport signature of such surface states is a plateau that arrests the exponential divergence of the insulating bulk with decreasing temperature. This universal behaviour is observed in all TI candidates ranging from Bi2Te2Se to SmB6. Recently, extreme magnetoresistance (XMR) has been reported in several topological semimetals which exhibit TI universal resistivity behaviour only when breaking time reversal symmetry, a regime where TIs theoretically cease to exist. Among these materials, TaAs and NbP are nominated as Weyl semimetals owing to their lack of inversion symmetry, Cd3As2 is known as a Dirac semimetal owing to its linear band crossing at the Fermi level, and WTe2 is termed a resonant compensated semimetal owing to its perfect electron{\textendash}hole symmetry. Here we introduce LaSb, a simple rock-salt structure material that lacks broken inversion symmetry, perfect linear band crossing, and perfect electron{\textendash}hole symmetry yet exhibits all the exotic field-induced behaviours of these more complex semimetals. It shows a field-induced universal TI resistivity with a plateau at roughly 15 K, ultrahigh mobility of carriers in the plateau region, quantum oscillations with the angle dependence of a two-dimensional Fermi surface, and XMR of about one million percent at 9 T. Owing to its structural simplicity, LaSb represents an ideal model system to formulate a theoretical understanding of the exotic consequences of breaking time reversal symmetry in topological semimetals.},
language = {en},
number = {3},
urldate = {2016-03-09},
journal = {Nat Phys},
author = {Tafti, F. F. and Gibson, Q. D. and Kushwaha, S. K. and Haldolaarachchige, N. and Cava, R. J.},
month = mar,
year = {2016},
keywords = {Topological insulators},
pages = {272--277},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/AVTQJW5B/Tafti et al. - 2016 - Resistivity plateau and extreme magnetoresistance .pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/EAJZKC6K/nphys3581.html:text/html}
}
@inproceedings{kitaev_periodic_2009,
title = {Periodic table for topological insulators and superconductors},
volume = {1134},
url = {http://scitation.aip.org/content/aip/proceeding/aipcp/10.1063/1.3149495},
doi = {10.1063/1.3149495},
abstract = {Gapped phases of noninteracting fermions, with and without charge conservation and time-reversal symmetry, are classified using Bott periodicity. The symmetry and spatial dimension determines a general universality class, which corresponds to one of the 2 types of complex and 8 types of real Clifford algebras. The phases within a given class are further characterized by a topological invariant, an element of some Abelian group that can be 0, Z, or Z 2 . The interface between two infinite phases with different topological numbers must carry some gapless mode. Topological properties of finite systems are described in terms of K-homology. This classification is robust with respect to disorder, provided electron states near the Fermi energy are absent or localized. In some cases (e.g., integer quantum Hall systems) the K-theoretic classification is stable to interactions, but a counterexample is also given.},
urldate = {2016-03-22},
booktitle = {{AIP} {Conference} {Proceedings}},
publisher = {AIP Publishing},
author = {Kitaev, Alexei},
month = may,
year = {2009},
keywords = {Algebras, Insulators, Spatial dimensions, Superconductors},
pages = {22--30},
file = {Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/GPMV9DV3/1.html:text/html}
}
@article{liu_discovery_2014,
title = {Discovery of a {Three}-{Dimensional} {Topological} {Dirac} {Semimetal}, {Na}3Bi},
volume = {343},
copyright = {Copyright {\textcopyright} 2014, American Association for the Advancement of Science},
issn = {0036-8075, 1095-9203},
url = {http://science.sciencemag.org/content/343/6173/864},
doi = {10.1126/science.1245085},
abstract = {A 3D Graphene?
Discoveries of materials with exciting electronic properties have propelled condensed matter physics over the past decade. Two of the best-known examples, graphene and topological insulators, have something in common: a linear energy-momentum relationship{\textemdash}the Dirac dispersion{\textemdash}in their two-dimensional (2D) electronic states. Topological insulators also have a more mundane aspect of their electronic structure, characterized by a band gap. Another class of materials, topological Dirac semimetals, has been proposed that has a linear dispersion along all three momentum directions{\textemdash}a bulk Dirac cone; these materials are predicted to have intriguing electronic properties and to be related to other exotic states through quantum phase transitions. Liu et al. (p. 864, published online 16 January) detected such a state in the compound Na3Bi by using photoemission spectroscopy.
Three-dimensional (3D) topological Dirac semimetals (TDSs) represent an unusual state of quantum matter that can be viewed as {\textquotedblleft}3D graphene.{\textquotedblright} In contrast to 2D Dirac fermions in graphene or on the surface of 3D topological insulators, TDSs possess 3D Dirac fermions in the bulk. By investigating the electronic structure of Na3Bi with angle-resolved photoemission spectroscopy, we detected 3D Dirac fermions with linear dispersions along all momentum directions. Furthermore, we demonstrated the robustness of 3D Dirac fermions in Na3Bi against in situ surface doping. Our results establish Na3Bi as a model system for 3D TDSs, which can serve as an ideal platform for the systematic study of quantum phase transitions between rich topological quantum states.
Angle-resolved photoemission spectroscopy is used to detect bulk Dirac cones in a three-dimensional analog of graphene.
Angle-resolved photoemission spectroscopy is used to detect bulk Dirac cones in a three-dimensional analog of graphene.},
language = {en},
number = {6173},
urldate = {2016-03-22},
journal = {Science},
author = {Liu, Z. K. and Zhou, B. and Zhang, Y. and Wang, Z. J. and Weng, H. M. and Prabhakaran, D. and Mo, S.-K. and Shen, Z. X. and Fang, Z. and Dai, X. and Hussain, Z. and Chen, Y. L.},
month = feb,
year = {2014},
pmid = {24436183},
pages = {864--867},
file = {Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/H82ZRQRV/864.html:text/html}
}
@article{nielsen_adler-bell-jackiw_1983,
title = {The {Adler}-{Bell}-{Jackiw} anomaly and {Weyl} fermions in a crystal},
volume = {130},
issn = {0370-2693},
url = {http://www.sciencedirect.com/science/article/pii/0370269383915290},
doi = {10.1016/0370-2693(83)91529-0},
abstract = {The Adler-Bell-Jackiw (ABJ) axial anomaly is derived from the physical point of view as the production of Weyl particles and it is used to show the absence of the net production of particles for lattice regularized chirally invariant theories with locality. An analogy or a simulation is pointed out between the Weyl fermion theory and gapless semiconductors where two energy bands have pointlike degeneracies. For such materials, in the presence of parallel electric and strong magnetic fields, there exists an effect similar to the ABJ anomaly that is the movement of the electrons in the energy-momentum space from the neighborhood of one degeneracy point to another one. The longitudinal magneto-conduction becomes extremely strong.},
number = {6},
urldate = {2016-03-24},
journal = {Physics Letters B},
author = {Nielsen, H. B. and Ninomiya, Masao},
month = nov,
year = {1983},
pages = {389--396},
file = {ScienceDirect Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/8F4TJH59/0370269383915290.html:text/html}
}
@article{ali_crystal_2014,
title = {The {Crystal} and {Electronic} {Structures} of {Cd}3As2, the {Three}-{Dimensional} {Electronic} {Analogue} of {Graphene}},
volume = {53},
issn = {0020-1669},
url = {http://dx.doi.org/10.1021/ic403163d},
doi = {10.1021/ic403163d},
abstract = {The structure of Cd3As2, a high-mobility semimetal reported to host electrons that act as Dirac particles, is reinvestigated by single-crystal X-ray diffraction. It is found to be centrosymmetric rather than noncentrosymmetric as previously reported. It has a distorted superstructure of the antifluorite (M2X) structure type with a tetragonal unit cell of a = 12.633(3) and c = 25.427(7) {\r A} in the centrosymmetric I41/acd space group. The antifluorite superstructure can be envisioned as consisting of distorted Cd6?2 cubes (where ? = an empty cube vertex) in parallel columns, stacked with opposing chirality. Electronic structure calculations performed using the experimentally determined centrosymmetric structure are similar to those performed with the inversion symmetry absent but with the important implication that Cd3As2 is a three-dimensional (3D)-Dirac semimetal with no spin splitting; all bands are spin degenerate and there is a 4-fold degenerate bulk Dirac point at the Fermi energy along $\Gamma$?Z in the Brillouin zone. This makes Cd3As2 a 3D electronic analogue of graphene. Scanning tunneling microscopy experiments identify a 2 ? 2 surface reconstruction in the (112) cleavage plane of single crystals; needle crystals grow with a [110] long axis direction.},
number = {8},
urldate = {2016-03-23},
journal = {Inorg. Chem.},
author = {Ali, Mazhar N. and Gibson, Quinn and Jeon, Sangjun and Zhou, Brian B. and Yazdani, Ali and Cava, R. J.},
month = apr,
year = {2014},
pages = {4062--4067},
file = {ACS Full Text Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/EE8AMSB7/ic403163d.html:text/html}
}
@article{xu_discovery_2015,
title = {Discovery of a {Weyl} fermion semimetal and topological {Fermi} arcs},
volume = {349},
copyright = {Copyright {\textcopyright} 2015, American Association for the Advancement of Science},
issn = {0036-8075, 1095-9203},
url = {http://science.sciencemag.org/content/349/6248/613},
doi = {10.1126/science.aaa9297},
abstract = {Weyl physics emerges in the laboratory
Weyl fermions{\textemdash}massless particles with half-integer spin{\textemdash}were once mistakenly thought to describe neutrinos. Although not yet observed among elementary particles, Weyl fermions may exist as collective excitations in so-called Weyl semimetals. These materials have an unusual band structure in which the linearly dispersing valence and conduction bands meet at discrete {\textquotedblleft}Weyl points.{\textquotedblright} Xu et al. used photoemission spectroscopy to identify TaAs as a Weyl semimetal capable of hosting Weyl fermions. In a complementary study, Lu et al. detected the characteristic Weyl points in a photonic crystal. The observation of Weyl physics may enable the discovery of exotic fundamental phenomena.
Science, this issue p. 613 and 622
A Weyl semimetal is a new state of matter that hosts Weyl fermions as emergent quasiparticles and admits a topological classification that protects Fermi arc surface states on the boundary of a bulk sample. This unusual electronic structure has deep analogies with particle physics and leads to unique topological properties. We report the experimental discovery of a Weyl semimetal, tantalum arsenide (TaAs). Using photoemission spectroscopy, we directly observe Fermi arcs on the surface, as well as the Weyl fermion cones and Weyl nodes in the bulk of TaAs single crystals. We find that Fermi arcs terminate on the Weyl fermion nodes, consistent with their topological character. Our work opens the field for the experimental study of Weyl fermions in physics and materials science.
Angle-resolved photoemission is used to detect the topological surface states and bulk dispersion of the compound tantalum arsenide. [Also see Report by Lu et al.]
Angle-resolved photoemission is used to detect the topological surface states and bulk dispersion of the compound tantalum arsenide. [Also see Report by Lu et al.]},
language = {en},
number = {6248},
urldate = {2016-03-23},
journal = {Science},
author = {Xu, Su-Yang and Belopolski, Ilya and Alidoust, Nasser and Neupane, Madhab and Bian, Guang and Zhang, Chenglong and Sankar, Raman and Chang, Guoqing and Yuan, Zhujun and Lee, Chi-Cheng and Huang, Shin-Ming and Zheng, Hao and Ma, Jie and Sanchez, Daniel S. and Wang, BaoKai and Bansil, Arun and Chou, Fangcheng and Shibayev, Pavel P. and Lin, Hsin and Jia, Shuang and Hasan, M. Zahid},
month = aug,
year = {2015},
pmid = {26184916},
pages = {613--617},
file = {Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/NUWBXWEB/613.html:text/html}
}
@article{kitaev_unpaired_2001,
title = {Unpaired {Majorana} fermions in quantum wires},
volume = {44},
issn = {1063-7869},
url = {http://stacks.iop.org/1063-7869/44/i=10S/a=S29},
doi = {10.1070/1063-7869/44/10S/S29},
abstract = {Certain one-dimensional Fermi systems have an energy gap in the bulk spectrum while boundary states are described by one Majorana operator per boundary point. A finite system of length L possesses two ground states with an energy difference proportional to exp(- L / l 0 ) and different fermionic parities. Such systems can be used as qubits since they are intrinsically immune to decoherence. The property of a system to have boundary Majorana fermions is expressed as a condition on the bulk electron spectrum. The condition is satisfied in the presence of an arbitrary small energy gap induced by proximity of a three-dimensional p-wave superconductor, provided that the normal spectrum has an odd number of Fermi points in each half of the Brillouin zone (each spin component counts separately).},
language = {en},
number = {10S},
urldate = {2016-03-24},
journal = {Phys.-Usp.},
author = {Kitaev, A. Yu},
year = {2001},
pages = {131},
file = {IOP Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/TH6WC949/Kitaev - 2001 - Unpaired Majorana fermions in quantum wires.pdf:application/pdf}
}
@article{bukov_universal_2015,
title = {Universal high-frequency behavior of periodically driven systems: from dynamical stabilization to {Floquet} engineering},
volume = {64},
issn = {0001-8732},
shorttitle = {Universal high-frequency behavior of periodically driven systems},
url = {http://dx.doi.org/10.1080/00018732.2015.1055918},
doi = {10.1080/00018732.2015.1055918},
abstract = {We give a general overview of the high-frequency regime in periodically driven systems and identify three distinct classes of driving protocols in which the infinite-frequency Floquet Hamiltonian is not equal to the time-averaged Hamiltonian. These classes cover systems, such as the Kapitza pendulum, the Harper{\textendash}Hofstadter model of neutral atoms in a magnetic field, the Haldane Floquet Chern insulator and others. In all setups considered, we discuss both the infinite-frequency limit and the leading finite-frequency corrections to the Floquet Hamiltonian. We provide a short overview of Floquet theory focusing on the gauge structure associated with the choice of stroboscopic frame and the differences between stroboscopic and non-stroboscopic dynamics. In the latter case, one has to work with dressed operators representing observables and a dressed density matrix. We also comment on the application of Floquet Theory to systems described by static Hamiltonians with well-separated energy scales and, in particular, discuss parallels between the inverse-frequency expansion and the Schrieffer{\textendash}Wolff transformation extending the latter to driven systems.},
number = {2},
urldate = {2016-03-23},
journal = {Advances in Physics},
author = {Bukov, Marin and D'Alessio, Luca and Polkovnikov, Anatoli},
month = mar,
year = {2015},
pages = {139--226},
file = {Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/9UJ9EJ3I/00018732.2015.html:text/html}
}
@article{parameswaran_probing_2014,
title = {Probing the {Chiral} {Anomaly} with {Nonlocal} {Transport} in {Three}-{Dimensional} {Topological} {Semimetals}},
volume = {4},
url = {http://link.aps.org/doi/10.1103/PhysRevX.4.031035},
doi = {10.1103/PhysRevX.4.031035},
abstract = {Weyl semimetals are three-dimensional crystalline systems where pairs of bands touch at points in momentum space, termed Weyl nodes, that are characterized by a definite topological charge: the chirality. Consequently, they exhibit the Adler-Bell-Jackiw anomaly, which in this condensed-matter realization implies that the application of parallel electric (E) and magnetic (B) fields pumps electrons between nodes of opposite chirality at a rate proportional to E{\textperiodcentered}B. We argue that this pumping is measurable via nonlocal transport experiments, in the limit of weak internode scattering. Specifically, we show that as a consequence of the anomaly, applying a local magnetic field parallel to an injected current induces a valley imbalance that diffuses over long distances. A probe magnetic field can then convert this imbalance into a measurable voltage drop far from source and drain. Such nonlocal transport vanishes when the injected current and magnetic field are orthogonal and therefore serves as a test of the chiral anomaly. We further demonstrate that a similar effect should also characterize Dirac semimetals{\textemdash}recently reported to have been observed in experiments{\textemdash}where the coexistence of a pair of Weyl nodes at a single point in the Brillouin zone is protected by a crystal symmetry. Since the nodes are analogous to valley degrees of freedom in semiconductors, the existence of the anomaly suggests that valley currents in three-dimensional topological semimetals can be controlled using electric fields, which has potential practical {\textquotedblleft}valleytronic{\textquotedblright} applications.},
number = {3},
urldate = {2016-03-23},
journal = {Phys. Rev. X},
author = {Parameswaran, S. A. and Grover, T. and Abanin, D. A. and Pesin, D. A. and Vishwanath, A.},
month = sep,
year = {2014},
pages = {031035},
file = {APS Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/3EU7KEZG/PhysRevX.4.html:text/html;Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/CCH89RVT/Parameswaran et al. - 2014 - Probing the Chiral Anomaly with Nonlocal Transport.pdf:application/pdf}
}
@article{moll_chirality_2015,
title = {Chirality transfer dynamics in quantum orbits in the {Dirac} semi-metal {Cd}\$\_3\${As}\$\_2\$},
url = {http://arxiv.org/abs/1505.02817},
abstract = {Dirac semi-metals show a linear electronic dispersion in three dimension described by two copies of the Weyl equation, a theoretical description of massless relativistic fermions. At the surface of a crystal, the breakdown of fermion chirality is expected to produce topological surface states without any counterparts in high-energy physics nor conventional condensed matter systems, the so-called "Fermi Arcs". Here we present Shubnikov-de Haas oscillations involving the Fermi Arc states in Focused Ion Beam prepared microstructures of Cd\$\_3\$As\$\_2\$. Their unusual magnetic field periodicity and dependence on sample thickness can be well explained by recent theoretical work predicting novel quantum paths weaving the Fermi Arcs together with chiral bulk states, forming "Weyl orbits". In contrast to conventional cyclotron orbits, these are governed by the chiral bulk dynamics rather than the common momentum transfer due to the Lorentz force. Our observations provide evidence for direct access to the topological properties of charge in a transport experiment, a first step towards their potential application.},
urldate = {2016-03-23},
journal = {arXiv:1505.02817 [cond-mat]},
author = {Moll, Philip J. W. and Nair, Nityan L. and Helm, Tony and Potter, Andrew C. and Kimchi, Itamar and Vishwanath, Ashvin and Analytis, James G.},
month = may,
year = {2015},
note = {arXiv: 1505.02817},
keywords = {Condensed Matter - Materials Science, Condensed Matter - Mesoscale and Nanoscale Physics, Condensed Matter - Strongly Correlated Electrons},
annote = {Comment: 7 pages, 5 figures},
file = {arXiv\:1505.02817 PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/7DH8TMXD/Moll et al. - 2015 - Chirality transfer dynamics in quantum orbits in t.pdf:application/pdf;arXiv.org Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/983X2ACM/1505.html:text/html}
}
@article{fu_superconducting_2008,
title = {Superconducting {Proximity} {Effect} and {Majorana} {Fermions} at the {Surface} of a {Topological} {Insulator}},
volume = {100},
url = {http://link.aps.org/doi/10.1103/PhysRevLett.100.096407},
doi = {10.1103/PhysRevLett.100.096407},
abstract = {We study the proximity effect between an s-wave superconductor and the surface states of a strong topological insulator. The resulting two-dimensional state resembles a spinless px+ipy superconductor, but does not break time reversal symmetry. This state supports Majorana bound states at vortices. We show that linear junctions between superconductors mediated by the topological insulator form a nonchiral one-dimensional wire for Majorana fermions, and that circuits formed from these junctions provide a method for creating, manipulating, and fusing Majorana bound states.},
number = {9},
urldate = {2016-03-24},
journal = {Phys. Rev. Lett.},
author = {Fu, Liang and Kane, C. L.},
month = mar,
year = {2008},
pages = {096407},
file = {APS Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/H2MRGMIF/PhysRevLett.100.html:text/html}
}
@article{wang_floquet_2014,
title = {Floquet {Weyl} semimetal induced by off-resonant light},
volume = {105},
issn = {0295-5075},
url = {http://stacks.iop.org/0295-5075/105/i=1/a=17004},
doi = {10.1209/0295-5075/105/17004},
abstract = {We propose that a Floquet Weyl semimetal state can be induced in three-dimensional topological insulators, either non-magnetic or magnetic, by the application of off-resonant light. The virtual photon processes play a critical role in renormalizing the Dirac mass and so resulting in a topological semimetal with vanishing gap at Weyl points. The present mechanism via off-resonant light is quite different from that via on-resonant light, the latter being recently suggested to give rise to a Floquet topological state in ordinary band insulators.},
language = {en},
number = {1},
urldate = {2016-04-04},
journal = {EPL},
author = {Wang, Rui and Wang, Baigeng and Shen, Rui and Sheng, L. and Xing, D. Y.},
year = {2014},
pages = {17004}
}
@article{novoselov_two-dimensional_2005,
title = {Two-dimensional gas of massless {Dirac} fermions in graphene},
volume = {438},
copyright = {{\textcopyright} 2005 Nature Publishing Group},
issn = {0028-0836},
url = {http://www.nature.com/nature/journal/v438/n7065/abs/nature04233.html},
doi = {10.1038/nature04233},
abstract = {Quantum electrodynamics (resulting from the merger of quantum mechanics and relativity theory) has provided a clear understanding of phenomena ranging from particle physics to cosmology and from astrophysics to quantum chemistry. The ideas underlying quantum electrodynamics also influence the theory of condensed matter, but quantum relativistic effects are usually minute in the known experimental systems that can be described accurately by the non-relativistic Schr{\"o}dinger equation. Here we report an experimental study of a condensed-matter system (graphene, a single atomic layer of carbon) in which electron transport is essentially governed by Dirac's (relativistic) equation. The charge carriers in graphene mimic relativistic particles with zero rest mass and have an effective 'speed of light' c * 106 m s-1. Our study reveals a variety of unusual phenomena that are characteristic of two-dimensional Dirac fermions. In particular we have observed the following: first, graphene's conductivity never falls below a minimum value corresponding to the quantum unit of conductance, even when concentrations of charge carriers tend to zero; second, the integer quantum Hall effect in graphene is anomalous in that it occurs at half-integer filling factors; and third, the cyclotron mass m c of massless carriers in graphene is described by E = m c c * 2. This two-dimensional system is not only interesting in itself but also allows access to the subtle and rich physics of quantum electrodynamics in a bench-top experiment.},
language = {en},
number = {7065},
urldate = {2016-03-24},
journal = {Nature},
author = {Novoselov, K. S. and Geim, A. K. and Morozov, S. V. and Jiang, D. and Katsnelson, M. I. and Grigorieva, I. V. and Dubonos, S. V. and Firsov, A. A.},
month = nov,
year = {2005},
pages = {197--200},
file = {Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/QSBRMT4F/nature04233.html:text/html}
}
@article{bertsch_real-space_2000,
title = {Real-space, real-time method for the dielectric function},
volume = {62},
url = {http://link.aps.org/doi/10.1103/PhysRevB.62.7998},
doi = {10.1103/PhysRevB.62.7998},
abstract = {We present an algorithm to calculate the linear response of periodic systems in the time-dependent density functional theory, using a real-space representation of the electron wave functions and calculating the dynamics in real time. The real-space formulation increases the efficiency for calculating the interaction, and the real-time treatment decreases storage requirements and allows the entire frequency-dependent dielectric function to be calculated at once. We give as examples the dielectric functions of a simple metal, lithium, and an elemental insulator, diamond.},
number = {12},
urldate = {2016-04-05},
journal = {Phys. Rev. B},
author = {Bertsch, G. F. and Iwata, J.-I. and Rubio, Angel and Yabana, K.},
month = sep,
year = {2000},
pages = {7998--8002},
file = {APS Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/QH3N4C4P/PhysRevB.62.html:text/html;Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/EBGVIQU3/Bertsch et al. - 2000 - Real-space, real-time method for the dielectric fu.pdf:application/pdf}
}
@article{hsu_floquet-bloch_2006,
title = {Floquet-{Bloch} states, quasienergy bands, and high-order harmonic generation for single-walled carbon nanotubes under intense laser fields},
volume = {74},
url = {http://link.aps.org/doi/10.1103/PhysRevB.74.115406},
doi = {10.1103/PhysRevB.74.115406},
abstract = {We study the electronic states and nonlinear motion of $\pi$ electrons in an armchair nanotube driven by monochromatic intense laser fields with polarization parallel to the nanotube axis. The intensity and frequency (photon energy) of the applied laser fields are varied so their effect on the electrons can be understood. In each case, Floquet-Bloch theory is used to calculate the Floquet-Bloch states, quasienergy band, mean energy band, and electron current density. By summing up the current density of all occupied Floquet-Bloch states, the harmonic generation spectrum can be determined. We demonstrate that the deformation of quasienergy band and mean energy band is related to high-order harmonic generation. Only the states deviating from field-free eigenstates may contribute to high-order harmonic generation.},
number = {11},
urldate = {2016-03-24},
journal = {Phys. Rev. B},
author = {Hsu, Han and Reichl, L. E.},
month = sep,
year = {2006},
pages = {115406},
file = {APS Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/U67XV68R/PhysRevB.74.html:text/html}
}
@incollection{hanggi_driven_1998,
title = {Driven {Quantum} {Systems}},
isbn = {978-3-527-29261-5},
booktitle = {Quantum {Transport} and {Dissipation}},
publisher = {Wiley-VCH},
author = {H{\"a}nggi, Peter},
month = mar,
year = {1998},
keywords = {Energy dissipation, Quantum theory, Science / Physics / General, Science / Physics / Mathematical \& Computational, Science / Physics / Quantum Theory, Transport theory}
}
@article{hartwigsen_relativistic_1998,
title = {Relativistic separable dual-space {Gaussian} pseudopotentials from {H} to {Rn}},
volume = {58},
url = {http://link.aps.org/doi/10.1103/PhysRevB.58.3641},
doi = {10.1103/PhysRevB.58.3641},
abstract = {We generalize the concept of separable dual-space Gaussian pseudopotentials to the relativistic case. This allows us to construct this type of pseudopotential for the whole Periodic Table, and we present a complete table of pseudopotential parameters for all the elements from H to Rn. The relativistic version of this pseudopotential retains all the advantages of its nonrelativistic version. It is separable by construction, it is optimal for integration on a real-space grid, it is highly accurate, and, due to its analytic form, it can be specified by a very small number of parameters. The accuracy of the pseudopotential is illustrated by an extensive series of molecular calculations.},
number = {7},
urldate = {2016-03-24},
journal = {Phys. Rev. B},
author = {Hartwigsen, C. and Goedecker, S. and Hutter, J.},
month = aug,
year = {1998},
pages = {3641--3662},
file = {APS Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/NQ28FMJ6/PhysRevB.58.html:text/html}
}
@article{andrade_real-space_2015,
title = {Real-space grids and the {Octopus} code as tools for the development of new simulation approaches for electronic systems},
volume = {17},
issn = {1463-9084},
url = {http://pubs.rsc.org/en/content/articlelanding/2015/cp/c5cp00351b},
doi = {10.1039/C5CP00351B},
abstract = {Real-space grids are a powerful alternative for the simulation of electronic systems. One of the main advantages of the approach is the flexibility and simplicity of working directly in real space where the different fields are discretized on a grid, combined with competitive numerical performance and great potential for parallelization. These properties constitute a great advantage at the time of implementing and testing new physical models. Based on our experience with the Octopus code, in this article we discuss how the real-space approach has allowed for the recent development of new ideas for the simulation of electronic systems. Among these applications are approaches to calculate response properties, modeling of photoemission, optimal control of quantum systems, simulation of plasmonic systems, and the exact solution of the Schr{\"o}dinger equation for low-dimensionality systems.},
language = {en},
number = {47},
urldate = {2016-03-24},
journal = {Phys. Chem. Chem. Phys.},
author = {Andrade, Xavier and Strubbe, David and Giovannini, Umberto De and Larsen, Ask Hjorth and Oliveira, Micael J. T. and Alberdi-Rodriguez, Joseba and Varas, Alejandro and Theophilou, Iris and Helbig, Nicole and Verstraete, Matthieu J. and Stella, Lorenzo and Nogueira, Fernando and Aspuru-Guzik, Al{\'a}n and Castro, Alberto and Marques, Miguel A. L. and Rubio, Angel},
month = nov,
year = {2015},
pages = {31371--31396},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/TRSPQGNQ/Andrade et al. - 2015 - Real-space grids and the Octopus code as tools for.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/J9XM4MTK/C5CP00351B.html:text/html}
}
@article{lv_experimental_2015,
title = {Experimental {Discovery} of {Weyl} {Semimetal} {TaAs}},
volume = {5},
url = {http://link.aps.org/doi/10.1103/PhysRevX.5.031013},
doi = {10.1103/PhysRevX.5.031013},
abstract = {Weyl semimetals are a class of materials that can be regarded as three-dimensional analogs of graphene upon breaking time-reversal or inversion symmetry. Electrons in a Weyl semimetal behave as Weyl fermions, which have many exotic properties, such as chiral anomaly and magnetic monopoles in the crystal momentum space. The surface state of a Weyl semimetal displays pairs of entangled Fermi arcs at two opposite surfaces. However, the existence of Weyl semimetals has not yet been proved experimentally. Here, we report the experimental realization of a Weyl semimetal in TaAs by observing Fermi arcs formed by its surface states using angle-resolved photoemission spectroscopy. Our first-principles calculations, which match remarkably well with the experimental results, further confirm that TaAs is a Weyl semimetal.},
number = {3},
urldate = {2016-03-24},
journal = {Phys. Rev. X},
author = {Lv, B. Q. and Weng, H. M. and Fu, B. B. and Wang, X. P. and Miao, H. and Ma, J. and Richard, P. and Huang, X. C. and Zhao, L. X. and Chen, G. F. and Fang, Z. and Dai, X. and Qian, T. and Ding, H.},
month = jul,
year = {2015},
pages = {031013},
file = {APS Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/DE7EEKX9/PhysRevX.5.html:text/html;Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/SQSFAIRX/Lv et al. - 2015 - Experimental Discovery of Weyl Semimetal TaAs.pdf:application/pdf}
}
@article{zhang_dynamics_2014,
title = {Dynamics and {Control} in {Complex} {Transition} {Metal} {Oxides}},
volume = {44},
url = {http://dx.doi.org/10.1146/annurev-matsci-070813-113258},
doi = {10.1146/annurev-matsci-070813-113258},
abstract = {Advances in the synthesis, growth, and characterization of complex transition metal oxides coupled with new experimental techniques in ultrafast optical spectroscopy have ushered in an exciting era of dynamics and control in these materials. Experiments utilizing femtosecond optical pulses can initiate and probe dynamics of the spin, lattice, orbital, and charge degrees of freedom. Major goals include (a) determining how interaction and competition between the relevant degrees of freedom determine macroscopic functionality in transition metal oxides (TMOs) and (b) searching for hidden phases in TMOs by controlling dynamic trajectories in a complex and pliable energy landscape. Advances in creating intense pulses from the far-IR spectrum through the visible spectrum enable mode-selective excitation to facilitate exploration of these possibilities. This review covers recent developments in this emerging field and presents examples that include the cuprates, manganites, and vanadates.},
number = {1},
urldate = {2015-04-20},
journal = {Annual Review of Materials Research},
author = {Zhang, J. and Averitt, R.D.},
year = {2014},
keywords = {cuprate, manganite, terahertz, ultrafast, vanadate, vibrational},
pages = {19--43},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/FRME454V/Zhang und Averitt - 2014 - Dynamics and Control in Complex Transition Metal O.pdf:application/pdf}
}
@article{orenstein_ultrafast_2012,
title = {Ultrafast spectroscopy of quantum materials},
volume = {65},
issn = {0031-9228, 1945-0699},
url = {http://scitation.aip.org/content/aip/magazine/physicstoday/article/65/9/10.1063/PT.3.1717},
doi = {10.1063/PT.3.1717},
abstract = {Subpicosecond laser pulses can selectively excite modes of strongly correlated electron systems and controllably push materials from one ordered phase to another.},
language = {en},
number = {9},
urldate = {2015-04-27},
journal = {Physics Today},
author = {Orenstein, Joseph},
month = aug,
year = {2012},
pages = {44--50},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/F5HNAQ7Q/Orenstein - 2012 - Ultrafast spectroscopy of quantum materials.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/IJ3EHIG9/PT.3.html:text/html}
}
@article{wang_three-dimensional_2013,
title = {Three-dimensional {Dirac} semimetal and quantum transport in {Cd}\$\{\}\_\{3\}\${As}\$\{\}\_\{2\}\$},
volume = {88},
url = {http://link.aps.org/doi/10.1103/PhysRevB.88.125427},
doi = {10.1103/PhysRevB.88.125427},
abstract = {Based on the first-principles calculations, we recover the silent topological nature of Cd3As2, a well known semiconductor with high carrier mobility. We find that it is a symmetry-protected topological semimetal with a single pair of three-dimensional (3D) Dirac points in the bulk and nontrivial Fermi arcs on the surfaces. It can be driven into a topological insulator and a Weyl semimetal state by symmetry breaking, or into a quantum spin Hall insulator with a gap more than 100 meV by reducing dimensionality. We propose that the 3D Dirac cones in the bulk of Cd3As2 can support sizable linear quantum magnetoresistance even up to room temperature.},
number = {12},
urldate = {2016-03-24},
journal = {Phys. Rev. B},
author = {Wang, Zhijun and Weng, Hongming and Wu, Quansheng and Dai, Xi and Fang, Zhong},
month = sep,
year = {2013},
pages = {125427},
file = {APS Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/KF5KVNBD/PhysRevB.88.html:text/html}
}
@article{liu_stable_2014,
title = {A stable three-dimensional topological {Dirac} semimetal {Cd}3As2},
volume = {13},
copyright = {{\textcopyright} 2014 Nature Publishing Group},
issn = {1476-1122},
url = {http://www.nature.com/nmat/journal/v13/n7/abs/nmat3990.html},
doi = {10.1038/nmat3990},
abstract = {Three-dimensional (3D) topological Dirac semimetals (TDSs) are a recently proposed state of quantum matter that have attracted increasing attention in physics and materials science. A 3D TDS is not only a bulk analogue of graphene; it also exhibits non-trivial topology in its electronic structure that shares similarities with topological insulators. Moreover, a TDS can potentially be driven into other exotic phases (such as Weyl semimetals, axion insulators and topological superconductors), making it a unique parent compound for the study of these states and the phase transitions between them. Here, by performing angle-resolved photoemission spectroscopy, we directly observe a pair of 3D Dirac fermions in Cd3As2, proving that it is a model 3D TDS. Compared with other 3D TDSs, for example, $\beta$-cristobalite BiO2 (ref. 3) and Na3Bi (refs 4, 5), Cd3As2 is stable and has much higher Fermi velocities. Furthermore, by in situ doping we have been able to tune its Fermi energy, making it a flexible platform for exploring exotic physical phenomena.},
language = {en},
number = {7},
urldate = {2016-03-24},
journal = {Nat Mater},
author = {Liu, Z. K. and Jiang, J. and Zhou, B. and Wang, Z. J. and Zhang, Y. and Weng, H. M. and Prabhakaran, D. and Mo, S.-K. and Peng, H. and Dudin, P. and Kim, T. and Hoesch, M. and Fang, Z. and Dai, X. and Shen, Z. X. and Feng, D. L. and Hussain, Z. and Chen, Y. L.},
month = jul,
year = {2014},
keywords = {Electronic devices, Electronic properties and materials, Topological insulators},
pages = {677--681},
file = {Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/XEHQ4P26/nmat3990.html:text/html}
}
@article{runge_density-functional_1984,
title = {Density-{Functional} {Theory} for {Time}-{Dependent} {Systems}},
volume = {52},
url = {http://link.aps.org/doi/10.1103/PhysRevLett.52.997},
doi = {10.1103/PhysRevLett.52.997},
abstract = {A density-functional formalism comparable to the Hohenberg-Kohn-Sham theory of the ground state is developed for arbitrary time-dependent systems. It is proven that the single-particle potential v(r? t) leading to a given v-representable density n(r? t) is uniquely determined so that the corresponding map v{\textrightarrow}n is invertible. On the basis of this theorem, three schemes are derived to calculate the density: a set of hydrodynamical equations, a stationary action principle, and an effective single-particle Schr{\"o}dinger equation.},
number = {12},
urldate = {2016-04-05},
journal = {Phys. Rev. Lett.},
author = {Runge, Erich and Gross, E. K. U.},
month = mar,
year = {1984},
pages = {997--1000},
file = {APS Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/3XKNVTD2/PhysRevLett.52.html:text/html;Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/WZPIJW99/Runge und Gross - 1984 - Density-Functional Theory for Time-Dependent Syste.pdf:application/pdf}
}
@article{neupane_observation_2014,
title = {Observation of a three-dimensional topological {Dirac} semimetal phase in high-mobility {Cd}3As2},
volume = {5},
copyright = {{\textcopyright} 2014 Nature Publishing Group, a division of Macmillan Publishers Limited. All Rights Reserved.},
url = {http://www.nature.com/ncomms/2014/140507/ncomms4786/abs/ncomms4786.html},
doi = {10.1038/ncomms4786},
abstract = {Symmetry-broken three-dimensional (3D) topological Dirac semimetal systems with strong spin-orbit coupling can host many exotic Hall-like phenomena and Weyl fermion quantum transport. Here, using high-resolution angle-resolved photoemission spectroscopy, we performed systematic electronic structure studies on Cd3As2, which has been predicted to be the parent material, from which many unusual topological phases can be derived. We observe a highly linear bulk band crossing to form a 3D dispersive Dirac cone projected at the Brillouin zone centre by studying the (001)-cleaved surface. Remarkably, an unusually high in-plane Fermi velocity up to 1.5 {\texttimes} 106 ms-1 is observed in our samples, where the mobility is known up to 40,000 cm2 V-1s-1, suggesting that Cd3As2 can be a promising candidate as an anisotropic-hypercone (three-dimensional) high spin-orbit analogue of 3D graphene. Our discovery of the Dirac-like bulk topological semimetal phase in Cd3As2 opens the door for exploring higher dimensional spin-orbit Dirac physics in a real material.
View full text},
language = {en},
urldate = {2016-03-24},
journal = {Nat Commun},
author = {Neupane, Madhab and Xu, Su-Yang and Sankar, Raman and Alidoust, Nasser and Bian, Guang and Liu, Chang and Belopolski, Ilya and Chang, Tay-Rong and Jeng, Horng-Tay and Lin, Hsin and Bansil, Arun and Chou, Fangcheng and Hasan, M. Zahid},
month = may,
year = {2014},
keywords = {Condensed matter, Materials science, Physical sciences},
pages = {3786},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/DDPTF9BN/Neupane et al. - 2014 - Observation of a three-dimensional topological Dir.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/ZV2C7XFK/ncomms4786.html:text/html}
}
@article{liang_ultrahigh_2015,
title = {Ultrahigh mobility and giant magnetoresistance in the {Dirac} semimetal {Cd}3As2},
volume = {14},
copyright = {{\textcopyright} 2014 Nature Publishing Group},
issn = {1476-1122},
url = {http://www.nature.com/nmat/journal/v14/n3/full/nmat4143.html},
doi = {10.1038/nmat4143},
abstract = {Dirac and Weyl semimetals are 3D analogues of graphene in which crystalline symmetry protects the nodes against gap formation. Na3Bi and ?Cd3As2 were predicted to be Dirac semimetals, and recently confirmed to be so by photoemission experiments. Several novel transport properties in a magnetic field have been proposed for Dirac semimetals. Here, we report a property of ?Cd3As2 that was unpredicted, namely a remarkable protection mechanism that strongly suppresses backscattering in zero magnetic field. In single crystals, the protection results in ultrahigh mobility, 9 {\texttimes} 106 cm2 V-1 s-1 at 5 K. Suppression of backscattering results in a transport lifetime 104 times longer than the quantum lifetime. The lifting of this protection by the applied magnetic field leads to a very large magnetoresistance. We discuss how this may relate to changes to the Fermi surface induced by the applied magnetic field.},
language = {en},
number = {3},
urldate = {2016-03-24},
journal = {Nat Mater},
author = {Liang, Tian and Gibson, Quinn and Ali, Mazhar N. and Liu, Minhao and Cava, R. J. and Ong, N. P.},
month = mar,
year = {2015},
keywords = {Topological insulators},
pages = {280--284},
file = {Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/7R58QIZM/nmat4143.html:text/html}
}
@article{borisenko_experimental_2014,
title = {Experimental {Realization} of a {Three}-{Dimensional} {Dirac} {Semimetal}},
volume = {113},
url = {http://link.aps.org/doi/10.1103/PhysRevLett.113.027603},
doi = {10.1103/PhysRevLett.113.027603},
abstract = {We report the direct observation of the three-dimensional (3D) Dirac semimetal phase in cadmium arsenide (Cd3As2) by means of angle-resolved photoemission spectroscopy. We identify two momentum regions where electronic states that strongly disperse in all directions form narrow conelike structures, and thus prove the existence of the long sought 3D Dirac points. This electronic structure naturally explains why Cd3As2 has one of the highest known bulk electron mobilities. This realization of a 3D Dirac semimetal in Cd3As2 not only opens a direct path to a wide spectrum of applications, but also offers a robust platform for engineering topologically nontrivial phases including Weyl semimetals and quantum spin Hall systems.},
number = {2},
urldate = {2016-03-24},
journal = {Phys. Rev. Lett.},
author = {Borisenko, Sergey and Gibson, Quinn and Evtushinsky, Danil and Zabolotnyy, Volodymyr and B{\"u}chner, Bernd and Cava, Robert J.},
month = jul,
year = {2014},
pages = {027603},
file = {APS Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/QWTM4WIK/PhysRevLett.113.html:text/html}
}
@article{jeon_landau_2014,
title = {Landau quantization and quasiparticle interference in the three-dimensional {Dirac} semimetal {Cd}3As2},
volume = {13},
copyright = {{\textcopyright} 2014 Nature Publishing Group},
issn = {1476-1122},
url = {http://www.nature.com/nmat/journal/v13/n9/abs/nmat4023.html},
doi = {10.1038/nmat4023},
abstract = {Condensed-matter systems provide a rich setting to realize Dirac and Majorana fermionic excitations as well as the possibility to manipulate them for potential applications. It has recently been proposed that chiral, massless particles known as Weyl fermions can emerge in certain bulk materials or in topological insulator multilayers and give rise to unusual transport properties, such as charge pumping driven by a chiral anomaly. A pair of Weyl fermions protected by crystalline symmetry effectively forming a massless Dirac fermion has been predicted to appear as low-energy excitations in a number of materials termed three-dimensional Dirac semimetals. Here we report scanning tunnelling microscopy measurements at sub-kelvin temperatures and high magnetic fields on the II{\textendash}V semiconductor ?Cd3As2. We probe this system down to atomic length scales, and show that defects mostly influence the valence band, consistent with the observation of ultrahigh-mobility carriers in the conduction band. By combining Landau level spectroscopy and quasiparticle interference, we distinguish a large spin-splitting of the conduction band in a magnetic field and its extended Dirac-like dispersion above the expected regime. A model band structure consistent with our experimental findings suggests that for a magnetic field applied along the axis of the Dirac points, Weyl fermions are the low-energy excitations in ?Cd3As2.},
language = {en},
number = {9},
urldate = {2016-03-24},
journal = {Nat Mater},
author = {Jeon, Sangjun and Zhou, Brian B. and Gyenis, Andras and Feldman, Benjamin E. and Kimchi, Itamar and Potter, Andrew C. and Gibson, Quinn D. and Cava, Robert J. and Vishwanath, Ashvin and Yazdani, Ali},
month = sep,
year = {2014},
keywords = {Electronic properties and materials, Topological insulators},
pages = {851--856},
file = {Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/UI8WPIMF/nmat4023.html:text/html}
}
@incollection{lepine_short-pulse_2012,
series = {Lecture {Notes} in {Physics}},
title = {Short-{Pulse} {Physics}},
copyright = {{\textcopyright}2012 Springer-Verlag Berlin Heidelberg},
isbn = {9783642235177 9783642235184},
url = {http://link.springer.com/chapter/10.1007/978-3-642-23518-4_1},
abstract = {The last century has seen the development of coherent light sources that have pushed our capability to probe properties of matter to a high level of sophistication. Femtosecond (fs) laser technology has paved the way to what is known as ultrafast science and led, in particular, to the mature field of femtochemistry (Hertel 2006). Concurrently, short pulses allowed to reach unprecedented photo-excitation conditions in which the coherent absorption of a large number of photons occurs, producing highly nonlinear phenomena.},
language = {en},
number = {837},
urldate = {2016-04-05},
booktitle = {Fundamentals of {Time}-{Dependent} {Density} {Functional} {Theory}},
publisher = {Springer Berlin Heidelberg},
author = {L{\'e}pine, Franck},
editor = {Marques, Miguel A. L. and Maitra, Neepa T. and Nogueira, Fernando M. S. and Gross, E. K. U. and Rubio, Angel},
year = {2012},
note = {DOI: 10.1007/978-3-642-23518-4\_1},
keywords = {Atomic/Molecular Structure and Spectra, Condensed Matter Physics, Numerical and Computational Physics, Theoretical and Computational Chemistry},
pages = {3--14},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/DFAPTEJ2/L{\'e}pine - 2012 - Short-Pulse Physics.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/QA2R7T89/978-3-642-23518-4_1.html:text/html}
}
@article{zyuzin_topological_2012,
title = {Topological response in {Weyl} semimetals and the chiral anomaly},
volume = {86},
url = {http://link.aps.org/doi/10.1103/PhysRevB.86.115133},
doi = {10.1103/PhysRevB.86.115133},
abstract = {We demonstrate that topological transport phenomena, characteristic of Weyl semimetals, namely the semiquantized anomalous Hall effect and the chiral magnetic effect (equilibrium magnetic-field-driven current), may be thought of as two distinct manifestations of the same underlying phenomenon, the chiral anomaly. We show that the topological response in Weyl semimetals is fully described by a $\theta$ term in the action for the electromagnetic field, where $\theta$ is not a constant parameter, like, for example, in topological insulators, but is a field, which has a linear dependence on the space-time coordinates. We also show that the $\theta$ term and the corresponding topological response survive for sufficiently weak translational symmetry breaking perturbations, which open a gap in the spectrum of the Weyl semimetal, eliminating the Weyl nodes.},
number = {11},
urldate = {2016-03-24},
journal = {Phys. Rev. B},
author = {Zyuzin, A. A. and Burkov, A. A.},
month = sep,
year = {2012},
pages = {115133},
file = {APS Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/X3GIN6T5/PhysRevB.86.html:text/html}
}
@article{huang_observation_2015,
title = {Observation of the {Chiral}-{Anomaly}-{Induced} {Negative} {Magnetoresistance} in 3D {Weyl} {Semimetal} {TaAs}},
volume = {5},
url = {http://link.aps.org/doi/10.1103/PhysRevX.5.031023},
doi = {10.1103/PhysRevX.5.031023},
abstract = {Weyl semimetal is the three-dimensional analog of graphene. According to quantum field theory, the appearance of Weyl points near the Fermi level will cause novel transport phenomena related to chiral anomaly. In the present paper, we report the experimental evidence for the long-anticipated negative magnetoresistance generated by the chiral anomaly in a newly predicted time-reversal-invariant Weyl semimetal material TaAs. Clear Shubnikov de Haas (SdH) oscillations have been detected starting from a very weak magnetic field. Analysis of the SdH peaks gives the Berry phase accumulated along the cyclotron orbits as $\pi$, indicating the existence of Weyl points.},
number = {3},
urldate = {2016-03-24},
journal = {Phys. Rev. X},
author = {Huang, Xiaochun and Zhao, Lingxiao and Long, Yujia and Wang, Peipei and Chen, Dong and Yang, Zhanhai and Liang, Hui and Xue, Mianqi and Weng, Hongming and Fang, Zhong and Dai, Xi and Chen, Genfu},
month = aug,
year = {2015},
pages = {031023},
file = {APS Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/5HQ36W7B/PhysRevX.5.html:text/html;Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/7FCCVM5A/Huang et al. - 2015 - Observation of the Chiral-Anomaly-Induced Negative.pdf:application/pdf}
}
@incollection{botti_microscopic_2012,
series = {Lecture {Notes} in {Physics}},
title = {The {Microscopic} {Description} of a {Macroscopic} {Experiment}},
copyright = {{\textcopyright}2012 Springer-Verlag Berlin Heidelberg},
isbn = {9783642235177 9783642235184},
url = {http://link.springer.com/chapter/10.1007/978-3-642-23518-4_3},
abstract = {The interaction between electromagnetic radiation (or particles) and matter creates elementary excitations in an electronic system.},
language = {en},
number = {837},
urldate = {2016-04-05},
booktitle = {Fundamentals of {Time}-{Dependent} {Density} {Functional} {Theory}},
publisher = {Springer Berlin Heidelberg},
author = {Botti, Silvana and Gatti, Matteo},
editor = {Marques, Miguel A. L. and Maitra, Neepa T. and Nogueira, Fernando M. S. and Gross, E. K. U. and Rubio, Angel},
year = {2012},
note = {DOI: 10.1007/978-3-642-23518-4\_3},
keywords = {Atomic/Molecular Structure and Spectra, Condensed Matter Physics, Numerical and Computational Physics, Theoretical and Computational Chemistry},
pages = {29--50},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/2MD55ERU/Botti und Gatti - 2012 - The Microscopic Description of a Macroscopic Exper.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/9C9TV7SZ/978-3-642-23518-4_3.html:text/html}
}
@incollection{kummel_orbital_2012,
series = {Lecture {Notes} in {Physics}},
title = {Orbital {Functionals}},
copyright = {{\textcopyright}2012 Springer-Verlag Berlin Heidelberg},
isbn = {9783642235177 9783642235184},
url = {http://link.springer.com/chapter/10.1007/978-3-642-23518-4_6},
abstract = {Orbital functionals have developed into powerful tools of modern TDDFT as they allow to tackle two of the theory{\textquoteright}s most notorious problems: By explicitly using the orbitals, functionals that are free from electronic self-interaction and that incorporate particle number discontinuities in the ex-change{\textendash}correlation potential can be constructed. This chapter presents an overview of why orbital functionals are needed and of the different ways in which they can be employed. The problem of electronic self-interaction and the advantages and drawbacks of the Kohn{\textendash}Sham and generalized Kohn{\textendash}Sham way of using orbital functionals are addressed. The problem of the time-dependent optimized effective potential is discussed in detail, and the chapter closes by looking at a few examples of orbital functionals which have been successfully used in practice.},
language = {en},
number = {837},
urldate = {2016-04-05},
booktitle = {Fundamentals of {Time}-{Dependent} {Density} {Functional} {Theory}},
publisher = {Springer Berlin Heidelberg},
author = {K{\"u}mmel, Stephan},
editor = {Marques, Miguel A. L. and Maitra, Neepa T. and Nogueira, Fernando M. S. and Gross, E. K. U. and Rubio, Angel},
year = {2012},
note = {DOI: 10.1007/978-3-642-23518-4\_6},
keywords = {Atomic/Molecular Structure and Spectra, Condensed Matter Physics, Numerical and Computational Physics, Theoretical and Computational Chemistry},
pages = {125--138},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/G3B6XZJW/K{\"u}mmel - 2012 - Orbital Functionals.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/Z4HECSUI/978-3-642-23518-4_6.html:text/html}
}
@incollection{huotari_spectroscopy_2012,
series = {Lecture {Notes} in {Physics}},
title = {Spectroscopy in the {Frequency} {Domain}},
copyright = {{\textcopyright}2012 Springer-Verlag Berlin Heidelberg},
isbn = {9783642235177 9783642235184},
url = {http://link.springer.com/chapter/10.1007/978-3-642-23518-4_2},
abstract = {In the same way as we can not visit a distant extrasolar planet to study its properties, the atomic world lies beyond our direct reach. The human being is only capable of handling objects of a certain size{\textemdash}both the very large and the very small are outside of our immediate reach. In these cases we can only get information by sending probes and receiving messengers.},
language = {en},
number = {837},
urldate = {2016-04-05},
booktitle = {Fundamentals of {Time}-{Dependent} {Density} {Functional} {Theory}},
publisher = {Springer Berlin Heidelberg},
author = {Huotari, Simo},
editor = {Marques, Miguel A. L. and Maitra, Neepa T. and Nogueira, Fernando M. S. and Gross, E. K. U. and Rubio, Angel},
year = {2012},
note = {DOI: 10.1007/978-3-642-23518-4\_2},
keywords = {Atomic/Molecular Structure and Spectra, Condensed Matter Physics, Numerical and Computational Physics, Theoretical and Computational Chemistry},
pages = {15--28},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/DB8HBGJA/Huotari - 2012 - Spectroscopy in the Frequency Domain.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/KDW98ATD/978-3-642-23518-4_2.html:text/html}
}
@incollection{appel_open_2012,
series = {Lecture {Notes} in {Physics}},
title = {Open {Quantum} {Systems}: {A} {Stochastic} {Perspective}},
copyright = {{\textcopyright}2012 Springer-Verlag Berlin Heidelberg},
isbn = {9783642235177 9783642235184},
shorttitle = {Open {Quantum} {Systems}},
url = {http://link.springer.com/chapter/10.1007/978-3-642-23518-4_11},
abstract = {Time-dependent density-functional theory (TDDFT) provides an efficient approach for the study of excited state properties as well as the real-time dynamics of many-particle systems.},
language = {en},
number = {837},
urldate = {2016-04-05},
booktitle = {Fundamentals of {Time}-{Dependent} {Density} {Functional} {Theory}},
publisher = {Springer Berlin Heidelberg},
author = {Appel, Heiko},
editor = {Marques, Miguel A. L. and Maitra, Neepa T. and Nogueira, Fernando M. S. and Gross, E. K. U. and Rubio, Angel},
year = {2012},
note = {DOI: 10.1007/978-3-642-23518-4\_11},
keywords = {Atomic/Molecular Structure and Spectra, Condensed Matter Physics, Numerical and Computational Physics, Theoretical and Computational Chemistry},
pages = {231--247},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/NM9M7SI5/Appel - 2012 - Open Quantum Systems A Stochastic Perspective.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/RWJE6XVS/978-3-642-23518-4_11.html:text/html}
}
@incollection{strubbe_response_2012,
series = {Lecture {Notes} in {Physics}},
title = {Response {Functions} in {TDDFT}: {Concepts} and {Implementation}},
copyright = {{\textcopyright}2012 Springer-Verlag Berlin Heidelberg},
isbn = {9783642235177 9783642235184},
shorttitle = {Response {Functions} in {TDDFT}},
url = {http://link.springer.com/chapter/10.1007/978-3-642-23518-4_7},
abstract = {Many physical properties of interest about solids and molecules can be considered as the reaction of the system to an external perturbation, and can be expressed in terms of response functions, in time or frequency and in real or reciprocal space. Response functions in TDDFT can be calculated by a variety of methods.},
language = {en},
number = {837},
urldate = {2016-04-05},
booktitle = {Fundamentals of {Time}-{Dependent} {Density} {Functional} {Theory}},
publisher = {Springer Berlin Heidelberg},
author = {Strubbe, David A. and Lehtovaara, Lauri and Rubio, Angel and Marques, Miguel A. L. and Louie, Steven G.},
editor = {Marques, Miguel A. L. and Maitra, Neepa T. and Nogueira, Fernando M. S. and Gross, E. K. U. and Rubio, Angel},
year = {2012},
note = {DOI: 10.1007/978-3-642-23518-4\_7},
keywords = {Atomic/Molecular Structure and Spectra, Condensed Matter Physics, Numerical and Computational Physics, Theoretical and Computational Chemistry},
pages = {139--166},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/KWHQ6NQU/Strubbe et al. - 2012 - Response Functions in TDDFT Concepts and Implemen.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/ESEQZHZZ/978-3-642-23518-4_7.html:text/html}
}
@incollection{leeuwen_multicomponent_2012,
series = {Lecture {Notes} in {Physics}},
title = {Multicomponent {Density}-{Functional} {Theory}},
copyright = {{\textcopyright}2012 Springer-Verlag Berlin Heidelberg},
isbn = {9783642235177 9783642235184},
url = {http://link.springer.com/chapter/10.1007/978-3-642-23518-4_12},
abstract = {The coupling between electronic and nuclear motion plays an essential role in a wide range of physical phenomena.},
language = {en},
number = {837},
urldate = {2016-04-05},
booktitle = {Fundamentals of {Time}-{Dependent} {Density} {Functional} {Theory}},
publisher = {Springer Berlin Heidelberg},
author = {Leeuwen, Robert van and Gross, Eberhard K. U.},
editor = {Marques, Miguel A. L. and Maitra, Neepa T. and Nogueira, Fernando M. S. and Gross, E. K. U. and Rubio, Angel},
year = {2012},
note = {DOI: 10.1007/978-3-642-23518-4\_12},
keywords = {Atomic/Molecular Structure and Spectra, Condensed Matter Physics, Numerical and Computational Physics, Theoretical and Computational Chemistry},
pages = {249--263},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/XHE4GAVU/Leeuwen und Gross - 2012 - Multicomponent Density-Functional Theory.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/72KHMVP4/978-3-642-23518-4_12.html:text/html}
}
@incollection{wagner_exact_2012,
series = {Lecture {Notes} in {Physics}},
title = {Exact {Conditions} and {Their} {Relevance} in {TDDFT}},
copyright = {{\textcopyright}2012 Springer-Verlag Berlin Heidelberg},
isbn = {9783642235177 9783642235184},
url = {http://link.springer.com/chapter/10.1007/978-3-642-23518-4_5},
abstract = {This chapter is devoted to exact conditions in time-dependent density functional theory. Many conditions have been derived for the exact ground-state density functional, and several have played crucial roles in the construction of popular approximations. We believe that the reliability of the most fundamental approximation of any density functional theory, the local density approximation (LDA), is due to the exact conditions that it satisfies. Improved approximations should satisfy at least those conditions that LDA satisfies, plus others. (Which others is part of the art of functional approximation).},
language = {en},
number = {837},
urldate = {2016-04-05},
booktitle = {Fundamentals of {Time}-{Dependent} {Density} {Functional} {Theory}},
publisher = {Springer Berlin Heidelberg},
author = {Wagner, Lucas O. and Yang, Zeng-hui and Burke, Kieron},
editor = {Marques, Miguel A. L. and Maitra, Neepa T. and Nogueira, Fernando M. S. and Gross, E. K. U. and Rubio, Angel},
year = {2012},
note = {DOI: 10.1007/978-3-642-23518-4\_5},
keywords = {Atomic/Molecular Structure and Spectra, Condensed Matter Physics, Numerical and Computational Physics, Theoretical and Computational Chemistry},
pages = {101--123},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/RRWIWBGB/Wagner et al. - 2012 - Exact Conditions and Their Relevance in TDDFT.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/XV4ND93B/978-3-642-23518-4_5.html:text/html}
}
@incollection{tempel_open_2012,
series = {Lecture {Notes} in {Physics}},
title = {Open {Quantum} {Systems}: {Density} {Matrix} {Formalism} and {Applications}},
copyright = {{\textcopyright}2012 Springer-Verlag Berlin Heidelberg},
isbn = {9783642235177 9783642235184},
shorttitle = {Open {Quantum} {Systems}},
url = {http://link.springer.com/chapter/10.1007/978-3-642-23518-4_10},
abstract = {In its original formulation, TDDFT addresses the isolated dynamics of electronic systems evolving unitarily (Runge and Gross 1984). However, there exist many situations in which the electronic degrees of freedom are not isolated, but must be treated as a subsystem imbedded in a much larger thermal bath.},
language = {en},
number = {837},
urldate = {2016-04-05},
booktitle = {Fundamentals of {Time}-{Dependent} {Density} {Functional} {Theory}},
publisher = {Springer Berlin Heidelberg},
author = {Tempel, David G. and Yuen-Zhou, Joel and Aspuru-Guzik, Al{\'a}n},
editor = {Marques, Miguel A. L. and Maitra, Neepa T. and Nogueira, Fernando M. S. and Gross, E. K. U. and Rubio, Angel},
year = {2012},
note = {DOI: 10.1007/978-3-642-23518-4\_10},
keywords = {Atomic/Molecular Structure and Spectra, Condensed Matter Physics, Numerical and Computational Physics, Theoretical and Computational Chemistry},
pages = {211--229},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/ID8JRST9/Tempel et al. - 2012 - Open Quantum Systems Density Matrix Formalism and.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/VAS7ZSIQ/978-3-642-23518-4_10.html:text/html}
}
@incollection{gross_introduction_2012,
series = {Lecture {Notes} in {Physics}},
title = {Introduction to {TDDFT}},
copyright = {{\textcopyright}2012 Springer-Verlag Berlin Heidelberg},
isbn = {9783642235177 9783642235184},
url = {http://link.springer.com/chapter/10.1007/978-3-642-23518-4_4},
abstract = {Correlated electron motion plays a significant role in the spectra described in the previous chapters. Further, placing an atom, molecule or solid in a strong laser field reveals fascinating non-perturbative phenomena, such as non-sequential multiple-ionization (see Chap. 18), whose origins lie in the subtle ways electrons interact with each other.},
language = {en},
number = {837},
urldate = {2016-04-05},
booktitle = {Fundamentals of {Time}-{Dependent} {Density} {Functional} {Theory}},
publisher = {Springer Berlin Heidelberg},
author = {Gross, Eberhard K. U. and Maitra, Neepa T.},
editor = {Marques, Miguel A. L. and Maitra, Neepa T. and Nogueira, Fernando M. S. and Gross, E. K. U. and Rubio, Angel},
year = {2012},
note = {DOI: 10.1007/978-3-642-23518-4\_4},
keywords = {Atomic/Molecular Structure and Spectra, Condensed Matter Physics, Numerical and Computational Physics, Theoretical and Computational Chemistry},
pages = {53--99},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/95I2K9KR/Gross und Maitra - 2012 - Introduction to TDDFT.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/BSQ6XJV6/978-3-642-23518-4_4.html:text/html}
}
@incollection{ruggenthaler_beyond_2012,
series = {Lecture {Notes} in {Physics}},
title = {Beyond the {Runge}{\textendash}{Gross} {Theorem}},
copyright = {{\textcopyright}2012 Springer-Verlag Berlin Heidelberg},
isbn = {9783642235177 9783642235184},
url = {http://link.springer.com/chapter/10.1007/978-3-642-23518-4_9},
abstract = {The Runge{\textendash}Gross theorem (Runge and Gross, Phys Rev Lett, 52:997{\textendash}1000, 1984) states that for a given initial state the time-dependent density is a unique functional of the external potential. Let us elaborate a bit further on this point. Suppose we could solve the time-dependent Schr{\"o}dinger equation for a given many-body system, i.e. we specify an initial state {\textbar}$\Psi$0?{\textbar} {\textbackslash}Uppsi\_0 {\textbackslash}rangle at t=t0t=t\_0 and evolve the wavefunction in time using the Hamiltonian {\textasciicircum}H(t).\{{\textbackslash}hat\{H\}\} (t). Then, from the wave function, we can calculate the time-dependent density TeXn ({\textbackslash}user2\{r\},t). We can then ask the question whether exactly the same density TeXn({\textbackslash}user2\{r\},t) can be reproduced by an external potential TeXv{\textasciicircum}\{{\textbackslash}prime\}\_\{{\textbackslash}rm ext\} ({\textbackslash}user2\{r\},t) in a system with a different given initial state and a different two-particle interaction, and if so, whether this potential is unique (modulo a purely time-dependent function). The answer to this question is obviously of great importance for the construction of the time-dependent Kohn{\textendash}Sham equations. The Kohn{\textendash}Sham system has no two-particle interaction and differs in this respect from the fully interacting system.},
language = {en},
number = {837},
urldate = {2016-04-05},
booktitle = {Fundamentals of {Time}-{Dependent} {Density} {Functional} {Theory}},
publisher = {Springer Berlin Heidelberg},
author = {Ruggenthaler, Michael and Leeuwen, Robert van},
editor = {Marques, Miguel A. L. and Maitra, Neepa T. and Nogueira, Fernando M. S. and Gross, E. K. U. and Rubio, Angel},
year = {2012},
note = {DOI: 10.1007/978-3-642-23518-4\_9},
keywords = {Atomic/Molecular Structure and Spectra, Condensed Matter Physics, Numerical and Computational Physics, Theoretical and Computational Chemistry},
pages = {187--210},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/3W8B2CX6/Ruggenthaler und Leeuwen - 2012 - Beyond the Runge{\textendash}Gross Theorem.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/NDV3H2A4/978-3-642-23518-4_9.html:text/html}
}
@incollection{castro_quantum_2012,
series = {Lecture {Notes} in {Physics}},
title = {Quantum {Optimal} {Control}},
copyright = {{\textcopyright}2012 Springer-Verlag Berlin Heidelberg},
isbn = {9783642235177 9783642235184},
url = {http://link.springer.com/chapter/10.1007/978-3-642-23518-4_13},
abstract = {All applications of time-dependent density-functional theory (TDDFT) until now have attempted to describe the response of many-electron systems to external fields. Given its success in this task, it seems timely, therefore, to address the inverse problem: given a prescribed goal (e.g., the transfer of electronic charge to a given region in space, or the population of a given excited state), what is the external perturbation that achieves this goal in an optimal way? This is the problem studied by quantum optimal control theory (QOCT). The essentials of this theory make no assumption on the nature of the quantum system whose behaviour is being engineered, or on the particular methodology used to model the system.},
language = {en},
number = {837},
urldate = {2016-04-05},
booktitle = {Fundamentals of {Time}-{Dependent} {Density} {Functional} {Theory}},
publisher = {Springer Berlin Heidelberg},
author = {Castro, Alberto and Gross, Eberhard K. U.},
editor = {Marques, Miguel A. L. and Maitra, Neepa T. and Nogueira, Fernando M. S. and Gross, E. K. U. and Rubio, Angel},
year = {2012},
note = {DOI: 10.1007/978-3-642-23518-4\_13},
keywords = {Atomic/Molecular Structure and Spectra, Condensed Matter Physics, Numerical and Computational Physics, Theoretical and Computational Chemistry},
pages = {265--276},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/5NC63HKR/Castro und Gross - 2012 - Quantum Optimal Control.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/HXJKWQU5/978-3-642-23518-4_13.html:text/html}
}
@incollection{casida_non-bornoppenheimer_2012,
series = {Lecture {Notes} in {Physics}},
title = {Non-{Born}{\textendash}{Oppenheimer} {Dynamics} and {Conical} {Intersections}},
copyright = {{\textcopyright}2012 Springer-Verlag Berlin Heidelberg},
isbn = {9783642235177 9783642235184},
url = {http://link.springer.com/chapter/10.1007/978-3-642-23518-4_14},
abstract = {The area of excited-state dynamics is receiving increasing attention for a number of reasons. First the importance of photochemical processes in basic energy sciences, improved theoretical methods and the associated theoretical understanding of photochemical processes. Then there is the advent of femtosecond (and now attosecond) spectroscopy allowing access to more detailed experimental information about photochemical processes. Since photophysical and chemical processes are more complex than thermal (i.e., ground state) processes, simulations quickly become expensive and even unmanageable as the model system becomes increasingly realistic. With its combination of simplicity and yet relatively good accuracy, TDDFT has been finding an increasingly important role to play in this rapidly developing field. After reviewing some basic ideas from photophysics and photochemistry, this chapter will cover some of the strengths and weaknesses of TDDFT for modeling photoprocesses.},
language = {en},
number = {837},
urldate = {2016-04-05},
booktitle = {Fundamentals of {Time}-{Dependent} {Density} {Functional} {Theory}},
publisher = {Springer Berlin Heidelberg},
author = {Casida, Mark E. and Natarajan, Bhaarathi and Deutsch, Thierry},
editor = {Marques, Miguel A. L. and Maitra, Neepa T. and Nogueira, Fernando M. S. and Gross, E. K. U. and Rubio, Angel},
year = {2012},
note = {DOI: 10.1007/978-3-642-23518-4\_14},
keywords = {Atomic/Molecular Structure and Spectra, Condensed Matter Physics, Numerical and Computational Physics, Theoretical and Computational Chemistry},
pages = {279--299},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/5XZ5XREF/Casida et al. - 2012 - Non-Born{\textendash}Oppenheimer Dynamics and Conical Intersec.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/AVVFWKTQ/978-3-642-23518-4_14.html:text/html}
}
@incollection{maitra_memory:_2012,
series = {Lecture {Notes} in {Physics}},
title = {Memory: {History} , {Initial}-{State} {Dependence} , and {Double}-{Excitations}},
copyright = {{\textcopyright}2012 Springer-Verlag Berlin Heidelberg},
isbn = {9783642235177 9783642235184},
shorttitle = {Memory},
url = {http://link.springer.com/chapter/10.1007/978-3-642-23518-4_8},
abstract = {In ground-state DFT, the fact that the xc potential is a functional of the density is a direct consequence of the one-to-one mapping between ground-state densities and potentials. In TDDFT, the one-to-one mapping is between densities and potentials for a given initial state. This means that the potentials, most generally, are functionals of the initial state of the system, as well as of the density; and, not just of the instantaneous density, but of its entire history.},
language = {en},
number = {837},
urldate = {2016-04-05},
booktitle = {Fundamentals of {Time}-{Dependent} {Density} {Functional} {Theory}},
publisher = {Springer Berlin Heidelberg},
author = {Maitra, Neepa T.},
editor = {Marques, Miguel A. L. and Maitra, Neepa T. and Nogueira, Fernando M. S. and Gross, E. K. U. and Rubio, Angel},
year = {2012},
note = {DOI: 10.1007/978-3-642-23518-4\_8},
keywords = {Atomic/Molecular Structure and Spectra, Condensed Matter Physics, Numerical and Computational Physics, Theoretical and Computational Chemistry},
pages = {167--184},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/RX6RFV72/Maitra - 2012 - Memory History , Initial-State Dependence , and D.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/9VEHH8ZV/978-3-642-23518-4_8.html:text/html}
}
@incollection{baroni_liouville-lanczos_2012,
series = {Lecture {Notes} in {Physics}},
title = {The {Liouville}-{Lanczos} {Approach} to {Time}-{Dependent} {Density}-{Functional} ({Perturbation}) {Theory}},
copyright = {{\textcopyright}2012 Springer-Verlag Berlin Heidelberg},
isbn = {9783642235177 9783642235184},
url = {http://link.springer.com/chapter/10.1007/978-3-642-23518-4_19},
abstract = {Most current implementations of time-dependent density-functional theory are designed to deal with the lowest-lying portion of the spectrum (often just a few of the very first discrete lines) of systems consisting of up to a few tens of atoms. We introduce a method that allows for the simulation of extended portions of the spectrum of systems virtually of the same size as possibly treatable with state-of-art ground-state DFT techniques.},
language = {en},
number = {837},
urldate = {2016-04-05},
booktitle = {Fundamentals of {Time}-{Dependent} {Density} {Functional} {Theory}},
publisher = {Springer Berlin Heidelberg},
author = {Baroni, Stefano and Gebauer, Ralph},
editor = {Marques, Miguel A. L. and Maitra, Neepa T. and Nogueira, Fernando M. S. and Gross, E. K. U. and Rubio, Angel},
year = {2012},
note = {DOI: 10.1007/978-3-642-23518-4\_19},
keywords = {Atomic/Molecular Structure and Spectra, Condensed Matter Physics, Numerical and Computational Physics, Theoretical and Computational Chemistry},
pages = {375--390},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/8RGJGIIM/Baroni und Gebauer - 2012 - The Liouville-Lanczos Approach to Time-Dependent D.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/U8A2UEN6/978-3-642-23518-4_19.html:text/html}
}
@incollection{kurth_electronic_2012,
series = {Lecture {Notes} in {Physics}},
title = {Electronic {Transport}},
copyright = {{\textcopyright}2012 Springer-Verlag Berlin Heidelberg},
isbn = {9783642235177 9783642235184},
url = {http://link.springer.com/chapter/10.1007/978-3-642-23518-4_17},
language = {en},
number = {837},
urldate = {2016-04-05},
booktitle = {Fundamentals of {Time}-{Dependent} {Density} {Functional} {Theory}},
publisher = {Springer Berlin Heidelberg},
author = {Kurth, Stefan},
editor = {Marques, Miguel A. L. and Maitra, Neepa T. and Nogueira, Fernando M. S. and Gross, E. K. U. and Rubio, Angel},
year = {2012},
note = {DOI: 10.1007/978-3-642-23518-4\_17},
keywords = {Atomic/Molecular Structure and Spectra, Condensed Matter Physics, Numerical and Computational Physics, Theoretical and Computational Chemistry},
pages = {337--350},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/JDWEU8MA/Kurth - 2012 - Electronic Transport.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/73DUSTBR/978-3-642-23518-4_17.html:text/html}
}
@incollection{alonso_combination_2012,
series = {Lecture {Notes} in {Physics}},
title = {On the {Combination} of {TDDFT} with {Molecular} {Dynamics}: {New} {Developments}},
copyright = {{\textcopyright}2012 Springer-Verlag Berlin Heidelberg},
isbn = {9783642235177 9783642235184},
shorttitle = {On the {Combination} of {TDDFT} with {Molecular} {Dynamics}},
url = {http://link.springer.com/chapter/10.1007/978-3-642-23518-4_15},
abstract = {In principle, we should not need the time-dependent extension of density-functional theory (TDDFT) for excitations.},
language = {en},
number = {837},
urldate = {2016-04-05},
booktitle = {Fundamentals of {Time}-{Dependent} {Density} {Functional} {Theory}},
publisher = {Springer Berlin Heidelberg},
author = {Alonso, Jos{\'e} L. and Castro, Alberto and Echenique, Pablo and Rubio, Angel},
editor = {Marques, Miguel A. L. and Maitra, Neepa T. and Nogueira, Fernando M. S. and Gross, E. K. U. and Rubio, Angel},
year = {2012},
note = {DOI: 10.1007/978-3-642-23518-4\_15},
keywords = {Atomic/Molecular Structure and Spectra, Condensed Matter Physics, Numerical and Computational Physics, Theoretical and Computational Chemistry},
pages = {301--315},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/7WQ9R4VW/Alonso et al. - 2012 - On the Combination of TDDFT with Molecular Dynamic.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/GRIVQKEZ/978-3-642-23518-4_15.html:text/html}
}
@incollection{lehtovaara_projector_2012,
series = {Lecture {Notes} in {Physics}},
title = {The {Projector} {Augmented} {Wave} {Method}},
copyright = {{\textcopyright}2012 Springer-Verlag Berlin Heidelberg},
isbn = {9783642235177 9783642235184},
url = {http://link.springer.com/chapter/10.1007/978-3-642-23518-4_20},
abstract = {DFT and TDDFT calculations are computationally intensive, and therefore, many different strategies are employed to reduce the computational burden. As the cost of a (TD)DFT calculation depends heavily on the number of degrees of freedom and active electrons, both should be minimized to speed up calculations while still reproducing the chemical and physical properties of interest.},
language = {en},
number = {837},
urldate = {2016-04-05},
booktitle = {Fundamentals of {Time}-{Dependent} {Density} {Functional} {Theory}},
publisher = {Springer Berlin Heidelberg},
author = {Lehtovaara, Lauri},
editor = {Marques, Miguel A. L. and Maitra, Neepa T. and Nogueira, Fernando M. S. and Gross, E. K. U. and Rubio, Angel},
year = {2012},
note = {DOI: 10.1007/978-3-642-23518-4\_20},
keywords = {Atomic/Molecular Structure and Spectra, Condensed Matter Physics, Numerical and Computational Physics, Theoretical and Computational Chemistry},
pages = {391--400},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/AJZKCDVC/Lehtovaara - 2012 - The Projector Augmented Wave Method.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/F93WC9JD/978-3-642-23518-4_20.html:text/html}
}
@incollection{rappoport_excited-state_2012,
series = {Lecture {Notes} in {Physics}},
title = {Excited-{State} {Properties} and {Dynamics}},
copyright = {{\textcopyright}2012 Springer-Verlag Berlin Heidelberg},
isbn = {9783642235177 9783642235184},
url = {http://link.springer.com/chapter/10.1007/978-3-642-23518-4_16},
abstract = {Structures and dynamics of electronically excited states of molecules play a central role in our understanding and modeling of molecular photophysics and photochemistry. Given the enormous success of density functional based methods for molecular ground-state properties, it is desirable to have methods at our disposal for computing excited-state forces and other first-order properties in the framework of DFT.},
language = {en},
number = {837},
urldate = {2016-04-05},
booktitle = {Fundamentals of {Time}-{Dependent} {Density} {Functional} {Theory}},
publisher = {Springer Berlin Heidelberg},
author = {Rappoport, Dmitrij and Hutter, J{\"u}rg},
editor = {Marques, Miguel A. L. and Maitra, Neepa T. and Nogueira, Fernando M. S. and Gross, E. K. U. and Rubio, Angel},
year = {2012},
note = {DOI: 10.1007/978-3-642-23518-4\_16},
keywords = {Atomic/Molecular Structure and Spectra, Condensed Matter Physics, Numerical and Computational Physics, Theoretical and Computational Chemistry},
pages = {317--336},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/G9E5GHAM/Rappoport und Hutter - 2012 - Excited-State Properties and Dynamics.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/KQIGMH32/978-3-642-23518-4_16.html:text/html}
}
@incollection{ullrich_atoms_2012,
series = {Lecture {Notes} in {Physics}},
title = {Atoms and {Molecules} in {Strong} {Laser} {Fields}},
copyright = {{\textcopyright}2012 Springer-Verlag Berlin Heidelberg},
isbn = {9783642235177 9783642235184},
url = {http://link.springer.com/chapter/10.1007/978-3-642-23518-4_18},
abstract = {The interactions of superstrong and ultrashort laser pulses with atoms and molecules have been a subject of great interest over the past two decades, as reflected in many books and review articles. The beginning of the twenty-first century is witnessing the development of several large- and medium-scale experimental facilities dedicated to the generation of laser light with unprecedented capabilities. The frequency spectrum covered by these new light sources ranges from the infrared up to the extreme ultraviolet and soft x-ray (produced in the FLASH free-electron laser facility at DESY). This calls for the development of new theoretical and computational tools to simulate laser-matter interactions at extreme conditions.},
language = {en},
number = {837},
urldate = {2016-04-05},
booktitle = {Fundamentals of {Time}-{Dependent} {Density} {Functional} {Theory}},
publisher = {Springer Berlin Heidelberg},
author = {Ullrich, Carsten A. and Bandrauk, Andr{\'e} D.},
editor = {Marques, Miguel A. L. and Maitra, Neepa T. and Nogueira, Fernando M. S. and Gross, E. K. U. and Rubio, Angel},
year = {2012},
note = {DOI: 10.1007/978-3-642-23518-4\_18},
keywords = {Atomic/Molecular Structure and Spectra, Condensed Matter Physics, Numerical and Computational Physics, Theoretical and Computational Chemistry},
pages = {351--371},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/7ZAAKQ4Q/Ullrich und Bandrauk - 2012 - Atoms and Molecules in Strong Laser Fields.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/RJNC9ZMC/978-3-642-23518-4_18.html:text/html}
}
@article{freericks_theoretical_2009,
title = {Theoretical {Description} of {Time}-{Resolved} {Photoemission} {Spectroscopy}: {Application} to {Pump}-{Probe} {Experiments}},
volume = {102},
shorttitle = {Theoretical {Description} of {Time}-{Resolved} {Photoemission} {Spectroscopy}},
url = {http://link.aps.org/doi/10.1103/PhysRevLett.102.136401},
doi = {10.1103/PhysRevLett.102.136401},
abstract = {The theory for time-resolved, pump-probe, photoemission spectroscopy and other pump-probe experiments is developed. The formal development is completely general, incorporating all of the nonequilibrium effects of the pump pulse and the finite time width of the probe pulse, and including possibilities for taking into account band structure and matrix element effects, surface states, and the interaction of the photoexcited electrons with the system leading to corrections to the sudden approximation. We also illustrate the effects of windowing that arise from the finite width of the probe pulse in a simple model system by assuming the quasiequilibrium approximation.},
number = {13},
urldate = {2016-02-02},
journal = {Phys. Rev. Lett.},
author = {Freericks, J. K. and Krishnamurthy, H. R. and Pruschke, Th.},
month = mar,
year = {2009},
pages = {136401},
file = {APS Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/PPUJ2W5R/PhysRevLett.102.html:text/html;Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/QUK5KH73/Freericks et al. - 2009 - Theoretical Description of Time-Resolved Photoemis.pdf:application/pdf}
}
@book{marques_fundamentals_2012,
series = {Lecture {Notes} in {Physics}},
title = {Fundamentals of time-dependent density functional theory},
volume = {837},
publisher = {Springer, Berlin},
editor = {Marques, M.A.L. and Maitra, N.T. and Nogueira, F and Gross, E.K.U. and Rubio, A.},
year = {2012}
}
@book{__????
}
@article{chan_when_2016,
title = {When {Chiral} {Photons} {Meet} {Chiral} {Fermions}: {Photoinduced} {Anomalous} {Hall} {Effects} in {Weyl} {Semimetals}},
volume = {116},
shorttitle = {When {Chiral} {Photons} {Meet} {Chiral} {Fermions}},
url = {http://link.aps.org/doi/10.1103/PhysRevLett.116.026805},
doi = {10.1103/PhysRevLett.116.026805},
abstract = {The Weyl semimetal is characterized by three-dimensional linear band touching points called Weyl nodes. These nodes come in pairs with opposite chiralities. We show that the coupling of circularly polarized photons with these chiral electrons generates a Hall conductivity without any applied magnetic field in the plane orthogonal to the light propagation. This phenomenon comes about because with all three Pauli matrices exhausted to form the three-dimensional linear dispersion, the Weyl nodes cannot be gapped. Rather, the net influence of chiral photons is to shift the positions of the Weyl nodes. Interestingly, the momentum shift is tightly correlated with the chirality of the node to produce a net anomalous Hall signal. Application of our proposal to the recently discovered TaAs family of Weyl semimetals leads to an order-of-magnitude estimate of the photoinduced Hall conductivity which is within the experimentally accessible range.},
number = {2},
urldate = {2016-04-06},
journal = {Phys. Rev. Lett.},
author = {Chan, Ching-Kit and Lee, Patrick A. and Burch, Kenneth S. and Han, Jung Hoon and Ran, Ying},
month = jan,
year = {2016},
pages = {026805},
file = {APS Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/MVNXRUSW/PhysRevLett.116.html:text/html;Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/CC9HTMEV/Chan et al. - 2016 - When Chiral Photons Meet Chiral Fermions Photoind.pdf:application/pdf}
}
@article{hosur_recent_2013,
series = {Topological insulators / {Isolants} {topologiquesTopological} insulators / {Isolants} topologiques},
title = {Recent developments in transport phenomena in {Weyl} semimetals},
volume = {14},
issn = {1631-0705},
url = {http://www.sciencedirect.com/science/article/pii/S1631070513001710},
doi = {10.1016/j.crhy.2013.10.010},
abstract = {The last decade has witnessed great advancements in the science and engineering of systems with unconventional band structures, seeded by studies of graphene and topological insulators. While the band structure of graphene simulates massless relativistic electrons in two dimensions, topological insulators have bands that wind non-trivially over momentum space in a certain abstract sense. Over the last couple of years, enthusiasm has been burgeoning in another unconventional and topological (although, not quite in the same sense as topological insulators) phase {\textendash} the Weyl semimetal. In this phase, electrons mimic Weyl fermions that are well known in high-energy physics, and inherit many of their properties, including an apparent violation of charge conservation known as the chiral anomaly. In this review, we recap some of the unusual transport properties of Weyl semimetals discussed in the literature so far, focusing on signatures whose roots lie in the anomaly. We also mention several proposed realizations of this phase in condensed matter systems, since they were what arguably precipitated activity on Weyl semimetals in the first place.},
number = {9{\textendash}10},
urldate = {2016-04-06},
journal = {Comptes Rendus Physique},
author = {Hosur, Pavan and Qi, Xiaoliang},
month = nov,
year = {2013},
keywords = {Chiral anomaly, Chiral transport, Dirac semimetal, Fermi arc, Weyl semimetal},
pages = {857--870},
file = {ScienceDirect Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/JQFCCE5Q/Hosur und Qi - 2013 - Recent developments in transport phenomena in Weyl.pdf:application/pdf;ScienceDirect Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/MEMBADX6/S1631070513001710.html:text/html}
}
@article{burkov_weyl_2011,
title = {Weyl {Semimetal} in a {Topological} {Insulator} {Multilayer}},
volume = {107},
url = {http://link.aps.org/doi/10.1103/PhysRevLett.107.127205},
doi = {10.1103/PhysRevLett.107.127205},
abstract = {We propose a simple realization of the three-dimensional (3D) Weyl semimetal phase, utilizing a multilayer structure, composed of identical thin films of a magnetically doped 3D topological insulator, separated by ordinary-insulator spacer layers. We show that the phase diagram of this system contains a Weyl semimetal phase of the simplest possible kind, with only two Dirac nodes of opposite chirality, separated in momentum space, in its band structure. This Weyl semimetal has a finite anomalous Hall conductivity and chiral edge states and occurs as an intermediate phase between an ordinary insulator and a 3D quantum anomalous Hall insulator. We find that the Weyl semimetal has a nonzero dc conductivity at zero temperature, but Drude weight vanishing as T2, and is thus an unusual metallic phase, characterized by a finite anomalous Hall conductivity and topologically protected edge states.},
number = {12},
urldate = {2016-04-06},
journal = {Phys. Rev. Lett.},
author = {Burkov, A. A. and Balents, Leon},
month = sep,
year = {2011},
pages = {127205},
file = {APS Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/72N5NEBU/PhysRevLett.107.html:text/html;Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/D27METKK/Burkov und Balents - 2011 - Weyl Semimetal in a Topological Insulator Multilay.pdf:application/pdf}
}
@article{yang_quantum_2011,
title = {Quantum {Hall} effects in a {Weyl} semimetal: {Possible} application in pyrochlore iridates},
volume = {84},
shorttitle = {Quantum {Hall} effects in a {Weyl} semimetal},
url = {http://link.aps.org/doi/10.1103/PhysRevB.84.075129},
doi = {10.1103/PhysRevB.84.075129},
abstract = {There has been much interest in pyrochlore iridates A2Ir2O7 where both strong spin-orbital coupling and strong correlation are present. A recent local density approximation calculation [X. Wan, A. M. Turner, A. Vishwanath, and S. Y. Savrasov, Phys. Rev. B 83, 205101 (2011)] suggests that the system is likely in a three-dimensional topological semimetallic phase: a Weyl semimetal. Such a system has zero carrier density and arrives at the quantum limit even in a weak magnetic field. In this paper, we discuss two quantum effects of this system in a magnetic field: a pressure-induced anomalous Hall effect and a magnetic-field-induced charge density wave at the pinned wave vector connecting Weyl nodes with opposite chiralities. A general formula of the anomalous Hall coefficients in a Weyl semimetal is also given. Both proposed effects can be probed by experiments in the near future and can be used to detect the Weyl semimetal phase.},
number = {7},
urldate = {2016-04-06},
journal = {Phys. Rev. B},
author = {Yang, Kai-Yu and Lu, Yuan-Ming and Ran, Ying},
month = aug,
year = {2011},
pages = {075129},
file = {APS Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/2FZV9TGA/PhysRevB.84.html:text/html}
}
@article{nielsen_absence_1981,
title = {Absence of neutrinos on a lattice},
volume = {185},
issn = {0550-3213},
url = {http://www.sciencedirect.com/science/article/pii/0550321381903618},
doi = {10.1016/0550-3213(81)90361-8},
abstract = {It is shown, by a homotopy theory argument, that for a general class of fermion theories on a Kogut-Susskind lattice an equal number of species (types) of left- and right-handed Weyl particles (neutrinos) necessarily appears in the continuum limit. We thus present a no-go theorem for putting theories of the weak interaction on a lattice. One of the most important consequences of our no-go theorem is that is not possible, in strong interaction models, to solve the notorious species doubling problem of Dirac fermions on a lattice in a chirally invariant way.},
number = {1},
urldate = {2016-04-08},
journal = {Nuclear Physics B},
author = {Nielsen, H. B. and Ninomiya, M.},
month = jul,
year = {1981},
pages = {20--40},
file = {ScienceDirect Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/ZIZV7TGQ/0550321381903618.html:text/html}
}
@article{ebihara_chiral_2015,
title = {Chiral pumping effect induced by rotating electric fields},
url = {http://arxiv.org/abs/1509.03673},
abstract = {We propose an experimental setup using 3D Dirac semimetals to access a novel phenomenon induced by the chiral anomaly. We show that the combination of a magnetic field and a circularly polarized laser induces a finite charge density with an accompanying axial current. This is because the circularly polarized laser breaks time-reversal symmetry and the Dirac point splits into two Weyl points, which results in an axial-vector field. We elucidate the appearance of the axial-vector field with the help of the Floquet theory by deriving an effective Hamiltonian for high-frequency electric fields. This anomalous charge density, i.e. the chiral pumping effect, is a phenomenon reminiscent of the chiral magnetic effect with a chiral chemical potential. We explicitly compute the pumped density and the axial-current expectation value. We also take account of coupling to the chiral magnetic effect to calculate a balanced distribution of charge and chirality in a material that behaves as a chiral battery.},
urldate = {2016-04-11},
journal = {arXiv:1509.03673 [cond-mat, physics:hep-ph]},
author = {Ebihara, Shu and Fukushima, Kenji and Oka, Takashi},
month = sep,
year = {2015},
note = {arXiv: 1509.03673},
keywords = {Condensed Matter - Strongly Correlated Electrons, High Energy Physics - Phenomenology},
annote = {Comment: 6 pages, 3 figures; a new section added to discuss coupling of the CPE and the CME, a wrong sign corrected, typos fixed, elaborated for better readability},
file = {arXiv\:1509.03673 PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/Z2WNTPTN/Ebihara et al. - 2015 - Chiral pumping effect induced by rotating electric.pdf:application/pdf;arXiv.org Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/CHIC6BVP/1509.html:text/html}
}
@article{li_chiral_2016,
title = {Chiral magnetic effect in {ZrTe}5},
volume = {advance online publication},
copyright = {{\textcopyright} 2016 Nature Publishing Group},
issn = {1745-2473},
url = {http://www.nature.com/nphys/journal/vaop/ncurrent/full/nphys3648.html},
doi = {10.1038/nphys3648},
abstract = {The chiral magnetic effect is the generation of an electric current induced by chirality imbalance in the presence of a magnetic field. It is a macroscopic manifestation of the quantum anomaly in relativistic field theory of chiral fermions (massless spin 1/2 particles with a definite projection of spin on momentum){\textemdash}a remarkable phenomenon arising from a collective motion of particles and antiparticles in the Dirac sea. The recent discovery of Dirac semimetals with chiral quasiparticles opens a fascinating possibility to study this phenomenon in condensed matter experiments. Here we report on the measurement of magnetotransport in zirconium pentatelluride, ZrTe5, that provides strong evidence for the chiral magnetic effect. Our angle-resolved photoemission spectroscopy experiments show that this material{\textquoteright}s electronic structure is consistent with a three-dimensional Dirac semimetal. We observe a large negative magnetoresistance when the magnetic field is parallel with the current. The measured quadratic field dependence of the magnetoconductance is a clear indication of the chiral magnetic effect. The observed phenomenon stems from the effective transmutation of a Dirac semimetal into a Weyl semimetal induced by parallel electric and magnetic fields that represent a topologically non-trivial gauge field background. We expect that the chiral magnetic effect may emerge in a wide class of materials that are near the transition between the trivial and topological insulators.},
language = {en},
urldate = {2016-04-11},
journal = {Nat Phys},
author = {Li, Qiang and Kharzeev, Dmitri E. and Zhang, Cheng and Huang, Yuan and Pletikosi{\'c}, I. and Fedorov, A. V. and Zhong, R. D. and Schneeloch, J. A. and Gu, G. D. and Valla, T.},
month = feb,
year = {2016},
keywords = {Electronic properties and materials, Theoretical nuclear physics, Theoretical particle physics, Theoretical physics},
file = {Full Text PDF:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/FBCPIGAK/Li et al. - 2016 - Chiral magnetic effect in ZrTe5.pdf:application/pdf;Snapshot:/Users/sentefmi/Library/Application Support/Zotero/Profiles/qipuo16i.default/zotero/storage/6I7Z9XQW/nphys3648.html:text/html}
}
