Microscopic modeling of photoluminescence of strongly disordered semiconductors

TL;DR

This paper develops a microscopic theory to describe photoluminescence in strongly disordered semiconductors, incorporating disorder and Coulomb interactions, and applies it to a one-dimensional model to analyze spectral properties.

Contribution

It introduces a modified microscopic model that accounts for both diagonal disorder and Coulomb interactions in disordered semiconductors, extending previous theories.

Findings

Luminescence and absorption spectra vary with disorder and temperature.

Thermodynamic relations and Stokes shift are characterized.

Radiative lifetime distribution is analyzed for different disorder levels.

Abstract

A microscopic theory for the luminescence of ordered semiconductors is modified to describe photoluminescence of strongly disordered semiconductors. The approach includes both diagonal disorder and the many-body Coulomb interaction. As a case study, the light emission of a correlated plasma is investigated numerically for a one-dimensional two-band tight-binding model. The band structure of the underlying ordered system is assumed to correspond to either a direct or an indirect semiconductor. In particular, luminescence and absorption spectra are computed for various levels of disorder and sample temperature to determine thermodynamic relations, the Stokes shift, and the radiative lifetime distribution.