Study of magnetism by total reflection angle X ray spectroscopy with spin polarized electron beam

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We intended to try not only to specify elements but also to get the information about magnetic moment of the atoms at the surface by careful measurements of the characteristic X ray intensities which arise from magnetic atoms in a ferromagnetic specimen by spin polarized incident electrons. An UHV system with a polarized electron source of GaAs was designed and manufactured by ourselves. The following three experiments have been done. 1) Intensive measurements of K_<alpha>, and K_<beta> characteristic X ray of Fe, Co, and Ni ferromagnetic metal exited by spin polarized electrons. No differences of K line intensities were observed between the cases with parallel and antiparallel spin polarization to the magnetization of the ferromagnetic samples. 2) Careful measurements of L line of Pd in a ferromagnetic Co-Pd alloy sample. The characteristic X ray for 4d*2p transition was identified, but there was hardly observed clear differences when the spin polarization of incident electrons was reversed. The polarization of 4d electrons of Pd in Co-Pd alloy may not be sufficient to be detected. 3) Appearance potential spectroscopy for L line of Fe. Soft X ray was detected by a channeltron behind a 750A Al filter. Appearance potential peak of L core excitation was observed. This peak intensities was dependent on the spin polarization of incident electrons with respect to the sample magnetization. Qualitative analysis will be done after further intensive experiments.