Band gap renormalization in photoexcited semiconductor quantum wire structures in the GW approximation

TL;DR

This paper studies how electron-electron and electron-phonon interactions affect the band gap in photoexcited semiconductor quantum wires using the GW approximation, revealing universal behavior and matching experimental data.

Contribution

It introduces a combined GW approach to analyze band gap renormalization considering both Coulomb and phonon interactions in quantum wires.

Findings

Calculated band gap renormalization agrees with experiments.

Normalized BGR shows approximate universality across parameters.

Method treats electron-electron and electron-phonon interactions on equal footing.

Abstract

We investigate the dynamical self-energy corrections of the electron-hole plasma due to electron-electron and electron-phonon interactions at the band edges of a quasi-one dimensional (1D) photoexcited electron-hole plasma. The leading-order $GW$ dynamical screening approximation is used in the calculation by treating electron-electron Coulomb interaction and electron-optical phonon Fr\"{o}hlich interaction on an equal footing. We calculate the exchange-correlation induced band gap renormalization (BGR) as a function of the electron-hole plasma density and the quantum wire width. The calculated BGR shows good agreement with existing experimental results, and the BGR normalized by the effective quasi-1D excitonic Rydberg exhibits an approximate one-parameter universality.