Giant optical anisotropy in cylindrical self-assembled InAs/GaAs quantum rings

TL;DR

This paper investigates how the shape and strain in InAs/GaAs quantum rings influence their electronic and optical properties, revealing giant optical anisotropy due to asymmetric biaxial strain.

Contribution

It introduces a detailed atomistic and many-particle analysis of quantum rings, highlighting the impact of shape transformation on optical anisotropy.

Findings

Giant optical anisotropy caused by asymmetric biaxial strain

Shape transformation from quantum dot to quantum ring affects electronic structure

Optical properties are highly sensitive to geometric changes

Abstract

Using a single-particle atomistic pseudopotential method followed by a many-particle configuration interaction method, we investigate the geometry, electronic structure and optical transitions of a self-assembled InAs/GaAs quantum ring (QR), changing its shape continously from a lens-shaped quantum dot (QD) to a nearly one dimensional ring. We find that the biaxial strain in the ring is strongly asymmetric in the plane perpendicular to the QR growth direction, leading to giant optical anisotropy.