Large optical gain from four-wave mixing instabilities in semiconductor quantum wells

TL;DR

This paper predicts significant optical gain in semiconductor quantum wells due to excitonic instabilities, using a microscopic many-particle theory to analyze four-wave mixing effects in a pump-probe setup.

Contribution

It introduces a microscopic theoretical model predicting large optical gain from four-wave mixing instabilities in quantum wells, highlighting excitonic effects.

Findings

Large optical gain predicted in quantum wells.

Instabilities depend on polarization and frequency.

Microscopic mechanisms elucidated.

Abstract

Based on a microscopic many-particle theory, we predict large optical gain in the probe and background-free four-wave mixing directions caused by excitonic instabilities in semiconductor quantum wells. For a single quantum well with radiative-decay limited dephasing in a typical pump-probe setup we discuss the microscopic driving mechanisms and polarization and frequency dependence of these instabilities.