Alfredo A. Correa edited Figure_ref_fig_stopping_power_shows__.tex  over 8 years ago

Commit id: a4fa496475137ec469a8104bfc01acf7de932346

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At higher velocities ($v > 4 ~\mathrm{a.u.}$) further disagreement stems from combined effect of the lack of explicit core electrons in the simulation and also size effects, as excitations of long wavelength plasma oscillation is constrained by the simulation supercell \cite{Schleife_2015}.   It is clear that a larger cell and eventually the inclusion of more core electrons would be necessary to obtain better agreement in this region.  The existence of plasma oscillations is detected in our simulations by persistent charge motion above a certain threshold velocity of $v \simeq 1~\mathrm{a.u.}$.   This plasma oscillations have a dramatic effects in the forces over individual $\mathrm{Cu}$ atoms near the track of the passing hydrogen.   This forces persist (and oscillate) even after the proton has passed.  Although experimental values have considerable vertical spread,   our calculated stopping power is on the low side for most of the points and also below the fitted by \textsc{Srim} model \cite{Ziegler_2010}.  While this was partially explained by taking into account off-channeling trajectories near the peak, there are possible intrinsic limitations of the theory used.