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arXiv · 1206.6035

Exact density-functional potentials for time-dependent quasiparticles

J. D. Ramsden·R. W. Godby
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Abstract

We calculate the exact Kohn-Sham potential that describes, within time-dependent density-functional theory, the propagation of an electron quasiparticle wavepacket of non-zero crystal momentum added to a ground-state model semiconductor. The potential is observed to have a highly nonlocal functional dependence on the charge density, in both space and time, giving rise to features entirely lacking in local or adiabatic approximations. The dependence of the non-equilibrium part of the Kohn-Sham electric field on the local current and charge density is identified as a key element of the correct Kohn-Sham functional.

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J. D. Ramsden, R. W. Godby. 2012-06-26. Exact density-functional potentials for time-dependent quasiparticles. https://doi.org/10.1103/physrevlett.109.036402

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