Exchange bias of a ferromagnetic semiconductor by a ferromagnetic metal

Abstract

We demonstrate an exchange bias in (Ga,Mn)As induced by antiferromagnetic coupling to a thin overlayer of Fe. Bias fields of up to 240 Oe are observed. Using element-specific x-ray magnetic circular dichroism measurements, we distinguish a strongly exchange coupled (Ga,Mn)As interface layer in addition to the biassed bulk of the (Ga,Mn)As film. The interface layer remains polarized at room temperature.