Theoretical study of angular-dependent L2,3-edge XMCD

We discuss the angular-dependent L2,3-edge X-ray magnetic circular dichroism (XMCD) spectra based on a relativistic full multiple-scattering theory, where 2-spinor formalism is used to describe spin-orbit coupling and spin dependent exchange scattering. We especially focus on the case of the transverse geometry where the incident X-ray propagation vector K is perpendicular to the direction of magnetization. Some numerical calculations show that the transverse XMCD δI can only be observed under low symmetry atomic arrangements around an X-ray absorbing atom. If there is an Cn axis around B(||z), we cannot observe the XMCD δI. Additional mirror symmetries, σxy and σyz also give rise to no δI. The calculated transverse XMCD spectra δI are considerably different from the conventional XMCD ΔI in accordance with an experimental result.