Anisotropy of in-plane hole g-factor in CdTe/ZnTe quantum dots

TL;DR

This paper introduces a universal optical method using dark excitons to analyze in-plane hole g-factor anisotropy in CdTe/ZnTe quantum dots, revealing diverse behaviors and emphasizing the importance of both isotropic and anisotropic contributions.

Contribution

The study presents a novel approach to measure heavy hole anisotropy via dark exciton polarization analysis in quantum dots.

Findings

Demonstrated a range of in-plane hole g-factor behaviors from isotropic to anisotropic.

Identified both isotropic and anisotropic contributions are significant in hole g-factor.

Applied method to multiple quantum dots showing diverse anisotropy characteristics.

Abstract

Optical studies of a bright exciton provide only limited information about the hole anisotropy in a quantum dot. In this work we present a universal method to study heavy hole anisotropy using a dark exciton in a moderate in-plane magnetic field. By analysis of the linear polarization of the dark exciton photoluminescence we identify both isotropic and anisotropic contributions to the hole g-factor. We employ this method for a number of individual self-assembled CdTe/ZnTe quantum dots, demonstrating a variety of behaviors of in-plane hole g-factor: from almost fully anisotropic to almost isotropic. We conclude that, in general, both contributions play an important role and neither contribution can be neglected.