Piezoelectric strain induced variation of the magnetic anisotropy in a high Curie temperature (Ga,Mn)As sample

TL;DR

This paper demonstrates that strain from a piezoelectric actuator can effectively and reversibly control magnetic anisotropy in high Curie temperature (Ga,Mn)As, enabling electrical manipulation of magnetic properties where gating fails.

Contribution

It introduces a method to control magnetic anisotropy in (Ga,Mn)As using piezoelectric strain, effective even at high doping levels and Curie temperatures.

Findings

Large reversible magnetic easy axis rotations achieved.

Quantitative relationship between strain and magnetic anisotropy established.

Comparison of magneto-transport and SQUID measurements highlights limitations.

Abstract

We show that effective electrical control of the magnetic properties in the ferromagnetic semiconductor (Ga,Mn)As is possible using the strain induced by a piezoelectric actuator even in the limit of high doping levels and high Curie temperatures, where direct electric gating is not possible. We demonstrate very large and reversible rotations of the magnetic easy axis. We compare the results obtained from magneto-transport and SQUID magnetometry measurements, extracting the dependence of the piezo-induced uniaxial magnetic anisotropy constant upon strain in both cases and detailing the limitations encountered in the latter approach.