Electronic noise of warm electrons in semiconductors from first-principles

TL;DR

This paper develops a first-principles, parameter-free theory to analyze electronic noise in semiconductors, revealing how microscopic relaxation processes influence noise characteristics.

Contribution

It introduces a novel first-principles formalism for electronic noise in semiconductors, avoiding adjustable parameters and linking spectral features to relaxation time scales.

Findings

Spectral features originate from momentum and energy relaxation time scales.

Optical phonon scattering dominates despite disparate relaxation processes.

Method applied successfully to GaAs, demonstrating practical utility.

Abstract

The ab-initio theory of low-field electronic transport properties such as carrier mobility in semiconductors is well-established. However, an equivalent treatment of electronic fluctuations about a non-equilibrium steady state, which are readily probed experimentally, remains less explored. Here, we report a first-principles theory of electronic noise for warm electrons in semiconductors. In contrast with typical numerical methods used for electronic noise, no adjustable parameters are required in the present formalism, with the electronic band structure and scattering rates calculated from first-principles. We demonstrate the utility of our approach by applying it to GaAs and show that spectral features in AC transport properties and noise originate from the disparate time scales of momentum and energy relaxation, despite the dominance of optical phonon scattering. Our formalism enables a parameter-free approach to probe the microscopic transport processes that give rise to electronic noise in semiconductors.