Strain balanced quantum posts

TL;DR

This paper introduces a strain compensation method using phosphorus incorporation to significantly increase the height of quantum posts, resulting in nanostructures with giant linear polarization anisotropy.

Contribution

A novel strain compensation technique for quantum posts that enhances their height and optical properties compared to existing methods.

Findings

Increased maximum height of quantum posts with phosphorous incorporation

Enhanced linear polarization anisotropy in emitted luminescence

Demonstration of strain compensation effectiveness

Abstract

Quantum posts are assembled by epitaxial growth of closely spaced quantum dot layers, modulating the composition of a semiconductor alloy, typically InGaAs. In contrast with most self-assembled nanostructures, the height of quantum posts can be controlled with nanometer precision, up to a maximum value limited by the accumulated stress due to the lattice mismatch. Here we present a strain compensation technique based on the controlled incorporation of phosphorous, which substantially increases the maximum attainable quantum post height. The luminescence from the resulting nanostructures presents giant linear polarization anisotropy.