Effect of uniaxial stress on the interference of polaritonic waves in wide quantum wells

TL;DR

This paper develops a theoretical model for polaritonic states in wide quantum wells under uniaxial stress, predicting how stress influences exciton-photon interference and spectral oscillations, with potential experimental observations at moderate pressures.

Contribution

It introduces a new theoretical framework for understanding how uniaxial stress affects polaritonic states and exciton-photon interference in wide quantum wells.

Findings

Spectral oscillations disappear and reappear with opposite phase under increasing pressure.

Stress induces $K$-linear terms in the exciton Hamiltonian affecting polariton behavior.

Effects are observable at pressures below 1 GPa for micron-scale wells.

Abstract

A theory of polaritonic states is developed for a nanostructure with a wide quantum well stressed perpendicular to the growth axis of the heterostructure. The role of the $K$-linear terms appearing in the exciton Hamiltonian under the stress is discussed. Exciton reflectance spectra are theoretically modeled for the nanostructure. It is predicted that the spectral oscillations caused by interference of the exciton-like and photon-like polariton modes disappear with the increase of applied pressure and then appear again with opposite phase relative to that observed at low pressure. Effects of gyrotropy and convergence of masses of excitons with heavy and light holes due to their mixing by the deformation is also considered. Numerical estimates performed for the GaAs wells show that these effects can be experimentally observed at pressure $P < 1$~GPa for the well widths of a fraction of micron.