Effects of impurity scattering on electron-phonon resonances in semiconductor superlattice high-field transport

TL;DR

This paper models high-field quantum transport in semiconductor superlattices, revealing how impurity scattering suppresses electron-phonon resonance peaks and highlighting their sensitivity to impurity characteristics.

Contribution

It introduces a non-perturbative Green's function approach to model impurity effects on electron-phonon resonances in superlattices across various electric fields.

Findings

Impurity scattering suppresses electron-phonon resonance peaks.

Resonance sensitivity depends on impurity size, strength, and concentration.

The method applies to both high and low electric fields.

Abstract

A non-equilibrium Green's function method is applied to model high-field quantum transport and electron-phonon resonances in semiconductor superlattices. The field-dependent density of states for elastic (impurity) scattering is found non-perturbatively in an approach which can be applied to both high and low electric fields. I-V curves, and specifically electron-phonon resonances, are calculated by treating the inelastic (LO phonon) scattering perturbatively. Calculations show how strong impurity scattering suppresses the electron-phonon resonance peaks in I-V curves, and their detailed sensitivity to the size, strength and concentration of impurities.