deletions | additions       diff --git a/Intro.tex b/Intro.tex  index 491f14a..345d4bc 100644  --- a/Intro.tex  +++ b/Intro.tex 
...
The creation of a scalable quantum-enabled machine, e.g. a quantum computer or a quantum communication system, requires the development of many elements, such as sources, memories, processing elements, measurement devices and a network able to inter-connect different resources \cite{Shapiro_2002, Kimble_2008}. Optical connections are indeed good candidates for the transmission of quantum information, in the form of flying qubits, single photons, or other nonclassical states, that can travel undisturbed over long distance. The major obstacle to such scheme is that often different elements work at different wavelengths.  Frequency translation ku\cite{Kumar_1990} provides a mean to shift and in general modify the energy of a quantum state while preserving the other quantum features (such as coherence \cite{Tanzilli_2005} and entanglement \cite{Ramelow_2012}), thus linking the different resources, e.g. IR flying qubits with efficient silicon detectors [Albota2004, Langrock2005, \cite{Albota_2004, Langrock_2005},  Vandevender2009, Ates2012] More recently, frequency translation has emerged as a mean to directly manipulate quantum in the full temporal and spectral space: by tailoring the pump spectrum and using concepts borrowed from parametric time-lens, both temporal compression [Agha2014] and magnification [Lavoie2013a] of quantum states can be implemented. While using temporally-shaped pump it is possible to select and convert different temporal modes , realizing an optical pulse gate [Reddy2014, Christensen15]. While sum- and difference-generation in χ(2) has been the base for many demonstrations, thanks to the high nonlinearity and ease of setup, frequency translation as been seen in other systems, including cross-phase modulation [Bradford2012, Matsuda2014], opto-mechanical hybrid systems [Hill2012, Preble2012], electro-optical modulation [Merolla1999], Alkali-vapor cells [Donvalkar2014], and microwave superconductor resonators [Zakka-Bajjani2011].   Among parametric χ(3) processes, Bragg Scattering can frequency translate quantum states without adding parametric noise [McKinstrie2005]. Follow up realizations include photonic crystal fiber [McKinstrie2005, McGuinness2010, \cite{Mejling_2012}], highly nonlinear fiber [Gnauck2006, Krupa12] and both SiN waveguides [Agha2013] and resonators [Li2015]. This implementation supports translation across any span of energy, enabling conversion between frequencies in the same communication band and small tuning. In addition, χ(3) implementations are compatible with integrated photonics.