Binding energy of localized biexcitons in quantum wells

TL;DR

This paper presents a variational calculation of the ground state energy of biexcitons in GaAs/AlGaAs quantum wells, modeling well width fluctuations and comparing results with experimental data.

Contribution

It introduces a model for biexciton trapping in quantum wells and compares theoretical results with experimental measurements.

Findings

Good agreement with experimental binding energies

Biexciton structure resembles H_2 molecule

Model effectively captures well width fluctuation effects

Abstract

A variational calculation of the ground state energy of a biexciton in a GaAs/AlGaAs quantum well is presented. The well width fluctuations leading to trapping of the biexcitons are modeled by a parabolic potential. The results obtained for different well widths are compared with recent experimental data. Good agreement is obtained both for the biexciton binding energy and for the Haynes factor. We find that the structure of a biexciton is similar to the one of the H_2 molecule.