Photoluminescence Spectroscopy of many-body Effects in Heavily Doped Al$_x$Ga$_{1-x}$As

TL;DR

This study uses photoluminescence spectroscopy to explore many-body effects like band gap narrowing and Fermi edge singularity in heavily doped Al$_x$Ga$_{1-x}$As, revealing how electron concentration and temperature influence these phenomena.

Contribution

It provides experimental evidence of many-body effects in heavily doped Al$_x$Ga$_{1-x}$As and highlights the role of nonequilibrated holes in enhancing FES-like features.

Findings

FES-like feature grows with increasing electron concentration.

FES-like feature is nonmonotonic with temperature and excitation intensity.

Small concentration of nonequilibrated holes enhances FES-like features.

Abstract

We present an experimental investigation of heavy doping-induced many-body effects such as band gap narrowing(BGN) and Fermi edge singularity(FES) in Al$_x$Ga$_{1-x}$As using photoluminescence(PL) spectroscopy. The band-to-band transition energy shifts to lower energies and FES-like feature in PL spectra grows with increasing electron concentration. We show that FES-like feature is a nonmonotonic function of temperature and excitation intensity. Our data lead us to suggest that a small concentration of nonequilibrated holes is required to enhance the FES-like feature in the PL spectra.