Spatial constraints on the source of uniaxial anisotropy in (Ga,Mn)As films

Zusammenfassung

We use time-resolved Kerr microscopy to perform ferromagnetic resonance experiments on nanostructured elements to show that strain is not the origin of the strong uniaxial in-plane anisotropy observed in (Ga, Mn) As films. From local angular dependent ferromagnetic resonance measurements we are able to extract the anisotropy constants. We observe no change of the strong uniaxial anisotropy in disks as small as 200 nm.