Surface and bulk contributions in magnetic linear dichroism in the angular dependence from ferromagnetic transition metals

The effects of photoelectron diffraction on the magnetic linear dichroism in the angular distribution (MLDAD) signal have been measured for experiments on crystalline iron and cobalt. Experimental photoemission data of Fe $3p$ and Co $3p$ core levels have been obtained in chiral geometry from bulk Fe(100) and from Co/Fe(100) and Fe/Co/Fe(100) epitaxial interfaces. A prominent forward-scattering peak is observed at normal emission and, correspondingly, a severe reduction of the Fe and Co magnetic dichroism asymmetry. The comparison between full multiple-scattering calculations and experimental results provides a rationale for understanding the role of photoelectron diffraction in MLDAD experiments. In this connection we show that both surface and bulk atoms contribute to the measured dichroic signal, but the line shape of bulk contribution to the spectra can be retrieved.