Adjustable anisotropy in ferromagnetic (Ga,Mn) (As,P) layered alloys

Abstract

We show that the extension of the widely studied GaMnAs system to quaternary ${\text{Ga}}_{1\ensuremath{-}\text{x}}{\text{Mn}}_{\text{x}}{\text{As}}_{1\ensuremath{-}\text{y}}{\text{P}}_{\text{y}}$ alloys allows to change and inverse the Mn doping induced uniaxial strain and thus the uniaxial magnetocrystalline anisotropy fields. In particular for typical Mn concentrations of $x=0.07$ the Mn dopant induced strain can be completely compensated by phosphorous alloying in the $y=0.06$ range and layers with both in-plane or out-of-plane easy axes of magnetizations with extremely low barriers for magnetization switching can be obtained.