Many-Body Dynamics and Exciton Formation Studied by Time-Resolved Photoluminescence

TL;DR

This paper investigates the dynamics of excitons and electron-hole plasma in materials using time-resolved photoluminescence, identifying regimes where emission is dominated by excitons or plasma, supported by microscopic theory.

Contribution

It introduces a method to distinguish exciton and plasma emission regimes and provides a microscopic theory to quantify bright excitons over time.

Findings

Identification of regimes dominated by excitons or plasma

Quantitative analysis of bright exciton fraction over time

Validation of microscopic theory with experimental data

Abstract

The dynamics of exciton and electron-hole plasma populations is studied via time-resolved photoluminescence after nonresonant excitation. By comparing the peak emission at the exciton resonance with the emission of the continuum, it is possible to experimentally identify regimes where the emission originates predominantly from exciton and/or plasma populations. The results are supported by a microscopic theory which allows one to extract the fraction of bright excitons as a function of time.