Cubic anisotropy in (Ga,Mn)As layers: Experiment and theory

The authors observe unreported features of magnetic anisotropy in the dilute ferromagnetic semiconductor (Ga,Mn)As. Magnetization and ferromagnetic resonance studies provide experimental evidence that, in a specific range of temperatures and hole concentrations, the <110> in-plane directions become the easy axes of the cubic contribution to magnetic anisotropy in (Ga,Mn)As(001). This result has significant supportive value for the theoretical description of ferromagnetism in (III,Mn)V dilute ferromagnetic semiconductors by the p-d Zener model. However, to provide a comprehensive quantitative account of these findings, incorporation of scattering broadening of the hole density of states, single-ion magnetic anisotropy of Mn, and disorder-driven nonuniformities of the carrier density have to be accomplished.