Manifestation of interface anisotropy in CdTe quantum wells

TL;DR

This study investigates how interface anisotropy affects optical properties in CdTe quantum wells, revealing birefringence in asymmetric structures and exciton resonances in symmetric ones through spectroscopic measurements.

Contribution

It demonstrates the manifestation of interface anisotropy in quantum wells via optical spectra, highlighting the role of barrier symmetry in exciton behavior and birefringence effects.

Findings

Birefringence observed in asymmetric barriers due to lower interface symmetry.

Exciton resonances detected in reflection spectra of symmetric barriers.

Light birefringence caused by interface anisotropy was discussed.

Abstract

Photoluminescence and polarized reflection spectra of quantum well structures with symmetric Cd$_{0.9}$Zn$_{0.1}$Te/CdTe/Cd$_{0.9}$Zn$_{0.1}$Te and asymmetric Cd$_{0.9}$Zn$_{0.1}$Te/CdTe/Cd$_{0.4}$Mg$_{0.6}$Te barriers were studied. The Stokes parameters of the reflected light from these structures were measured. In the structures with symmetric barriers, exciton resonances were found in the reflection spectra and were not present in the photoluminescence spectra. In structures with asymmetric barriers, in the region of exciton resonances, the phenomenon of light birefringence was detected, caused by a lower symmetry of the interfaces compared to the symmetry of bulk crystals. A discussion of both phenomena was given.