Annealing-induced changes of the magnetic anisotropy of (Ga,Mn)As epilayers

TL;DR

This study investigates how annealing temperature and time affect the magnetic anisotropy in (Ga,Mn)As epilayers, revealing a switch in anisotropy orientation linked to charge carrier concentration changes.

Contribution

It demonstrates the annealing-induced reorientation of magnetic anisotropy in (Ga,Mn)As epilayers and its dependence on charge carrier concentration.

Findings

Uniaxial magnetic anisotropy orientation changes from [-110] to [110] after annealing.

Both cubic and uniaxial anisotropies are linked to charge carrier concentration.

Annealing parameters control the magnetic anisotropy orientation.

Abstract

The dependence of the magnetic anisotropy of As-capped (Ga,Mn)As epilayers on the annealing parameters - temperature and time - has been investigated. A uniaxial magnetic anisotropy is evidenced, whose orientation with respect to the crystallographic axes changes upon annealing from [-110] for the as-grown samples to [110] for the annealed samples. Both cubic an uniaxial anisotropies are tightly linked to the concentration of charge carriers, the magnitude of which is controlled by the annealing process.