Uncompensated Moments in the MnPd/Fe Exchange Bias System

The element-specific magnetic structure of an epitaxially grown Mn 52 Pd 48 /Fe bilayer showing exchange bias was investigated with atomic-layer depth sensitivity at the antiferromagnet/ferromagnet interface by softx-ray magnetic circular dichroism and magnetic reflectivity. A complex magnetic interfacial configuration, consisting of a 2-monolayer-thick induced ferromagnetic region, and pinned uncompensated Mn moments that reach far deeper (~13 Å), both in the antiferromagnet, were found. For the latter, a direct relationship with the magnitude of the exchange bias is verified by similar measurements perpendicular to the field cooling direction.