Spin resolved resonant inverse photoemission

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In this year, we made spin resolved electron g^<uc>. The electron source of the g^<un> is made by Cs coated GaAsP, where Cs decreases the work function. This is NEA cathod type.The experiments were carried Out by the SXES spectrometer that was made by us. The RIPES measurement near Ce 4d absorption edge reveals the remarkable contrastive electronic structure at the bulk and surface state of CePd_7. The RIPES at Ce 4d * 4f edge is found to be a powerful method to investigate the surface 4f state. The bulk is alpha-like and the surface is gamma-like. The difference of the ground state configuration at the bulk and surface reflects the separate resonances. The extremely high Kondo temperature (kT_K-O.95 eV) of bulk expresses the very strong hybridization between the 4f and ligand electrons. Our results are consistent with the calculated results. Due to the large Ce-Ce spacing, the calculation within the framework of IAM seems to give a good agreement. The resonant enhancement of 4f-cross section makes it possible to distinguish between the specific contributions in the spectra near Fermi level. It is pointed out that the RIPES measurement around Ce 4d edge has high sensitivity to the surface. Also, the energy band scheme (LMTO) gives a qualitatively good agreement with the off resonance spectra, which are mainly of Ce 5d origin. However, band calculation underestimates the energy position of the Ce 5d component above the Fermi level by about 1.4 eV.