Phosphorous alloying: controlling the magnetic anisotropy in ferromagnetic (Ga,Mn)(As,P) Layers

TL;DR

This study investigates how phosphorous alloying in GaMnAs thin films influences magnetic anisotropy, enabling control over magnetic easy axes without significantly raising the critical temperature.

Contribution

It demonstrates that phosphorous alloying can tune magnetic anisotropy and easy axes in GaMnAs layers while maintaining ferromagnetism and stable critical temperatures.

Findings

Control of in-plane and out-of-plane magnetic easy axes through P alloying.

Magnetic anisotropy constants vary with temperature and P level.

Critical temperatures remain largely unaffected by P alloying.

Abstract

Phosphorous alloying of GaMnAs thin films has been used for the manipulation of the magnetic anisotropies in ferromagnetic Ga0.93Mn0.07As1-yPy layers. We have determined the anisotropy constants as a function of temperature for phosphorous alloying levels between 0 and 8.8 at % for a Mn doping level of ~ 7at%. We show that it is possible to obtain layers with robust ferromagnetism and either in-plane or out-of plane easy axes with small barriers for magnetization reorientation by phosphorous alloying with y< 6at% or y> 6at%. The critical temperatures are not significantly increased by the P alloying.