Influence of defects on the lattice constant of GaMnAs

TL;DR

This study investigates how main defects, specifically As antisites and Mn interstitials, affect the lattice constant of GaMnAs, revealing a defect balance and the impact of annealing on its structural properties.

Contribution

It provides experimental insights into the relationship between defect types and lattice parameters in GaMnAs, highlighting defect balance effects and annealing limitations.

Findings

Balance between Mn interstitials and As antisites affects lattice constant

Increased As antisites inhibit annealing-induced lattice reduction

Different defect balances lead to significant lattice parameter variations

Abstract

We study the influence of main compensating defects: As antisites and Mn interstitials, known to occur in GaMnAs ferromagnetic semiconductor, on its structural properties. Our experimental results show that there is a balance between Mn interstitial and As antisite defects, leading to the reduced density of one type of defect upon increased density of another defect. The significant differences in the lattice parameters of GaMnAs with the different balance between these two types of defects were observed. The annealing induced reduction of GaMnAs lattice constant is inhibited in the samples with large density of As antisites.