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arXiv · 0803.0368

Correlated electron-phonon transport from molecular dynamics with quantum baths

J. T. Lu·Jian-Sheng Wang
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Abstract

Based on generalized quantum Langevin equations for the tight-binding wave function amplitudes and lattice displacements, electron and phonon quantum transport are obtained exactly using molecular dynamics (MD) in the ballistic regime. The electron-phonon interactions can be handled with a quasi-classical approximation. Both charge and energy transport and their interplay can be studied. We compare the MD results with that of a fully quantum mechanical nonequilibrium Green's function (NEGF) approach for the electron currents. We find a ballistic to diffusive transition of the electron conduction in one dimensional chains as the chain length increases.

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J. T. Lu, Jian-Sheng Wang. 2008-06-06. Correlated electron-phonon transport from molecular dynamics with quantum baths. https://doi.org/10.1088/0953-8984%2F21%2F2%2F025503

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