Probing the spin and orbital high-field susceptibility of magnetic solids on the basis of theXMCD sum rules

Abstract

It is demonstrated that the magnetic circular dichroism in x-ray absorption (XMCD) canbe used to probe the spin and orbital high-field susceptibilities of spontaneously magneticsolids on the basis of the so-called XMCD sum rules. A corresponding theoreticaldescription is presented that is formulated in terms of the fully relativistic multiplescattering Green’s function formalism. Examples for the field-induced changesin XMCD spectra are given together with an application of the sum rules tothese spectra that demonstrates their relation to the high-field susceptibility.