Correlated electron-phonon transport from molecular dynamics with quantum baths

TL;DR

This paper presents an exact molecular dynamics approach using generalized quantum Langevin equations to study correlated electron-phonon transport, capturing ballistic to diffusive transition in 1D chains.

Contribution

It introduces a novel MD-based method for electron-phonon transport that incorporates quantum baths and compares favorably with NEGF results.

Findings

Ballistic to diffusive transition observed in electron conduction with increasing chain length.

MD results agree with NEGF for electron currents in the ballistic regime.

Method enables study of charge and energy transport interplay.

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.