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arXiv · 0706.1803

Electronic stopping power in insulators from first principles

J. M. Pruneda·D. Sanchez-Portal·A. Arnau·J. I. Juaristi·Emilio Artacho
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Abstract

Using time-dependent density-functional theory we calculate from first principles the rate of energy transfer from a moving proton or antiproton to the electrons of an insulating material, LiF. The behavior of the electronic stopping power versus projectile velocity displays an effective threshold velocity of ~0.2 a.u. for the proton, consistent with recent experimental observations, and also for the antiproton. The calculated proton/antiproton stopping-power ratio is ~2.4 at velocities slightly above the threshold (v~0.4 a.u.), as compared to the experimental value of 2.1. The projectile energy loss mechanism is observed to be stationary and extremely local.

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J. M. Pruneda, D. Sanchez-Portal, A. Arnau, J. I. Juaristi, Emilio Artacho. 2007-06-15. Electronic stopping power in insulators from first principles. https://doi.org/10.1103/physrevlett.99.235501

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