Atom specific surface magnetometry with linear magnetic dichroism in directional photoemission

A practical atom specific surface magnetometry can be based on the measure of magnetic dichroism in the angular distribution of core photoelectrons using linearly polarized synchrotron radiation. The magnetic dichroism effect on the photoemission intensity of 3p core levels of the ferromagnetic transition elements is as large as 46% in the case of Fe(100). The most efficient scheme for measuring the magnetic dichroism in photoemission requires two mirror experiments in chiral geometry, i.e. only two times more experiments than standard core level photoemission for surface chemical analysis. We describe the dichroism magnetometry and show examples for Fe, Co, Ni and Cr surfaces and interfaces, including the measurement of the temperature dependence of the Fe(100) surface magnetization and of the effect of S-segregation on the surface magnetic moment of iron.