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Spin pumping is an interfacial spin current generation from the ferromagnetic layer to the non-magnetic metal at its interface. The polarization of the pumped spin current J s ∝ m × m ˙ depends on the dynamics of the magnetic moment m . When the materials are based on light transition metals, mechanism behind the spin current transfer is dominated by the exchange interaction between spin of localized d-electrons and itinerant conduction electrons. In heavier transition metals, however, the interaction is not limited to the exchange interaction. The spin of the conduction electron can interact to its nuclear spin by means of hyperfine interaction, as observed in the shift of NMR frequency. By studying the spin polarization of conduction electron of the non-magnetic metallic layer due to a nuclear magnetic moment I of the ferromagnetic layer, we show that the hyperfine interaction can mediate the spin pumping. The polarization of the spin current generation is shown to have a similar form J s ∝ I × I ˙ . [ABSTRACT FROM AUTHOR]

We demonstrate spin-exchange optical pumping of Xe atoms with our newly made laser system. The new laser system was prepared to provide higher laser power required for the stable operation of spin maser oscillations in the Xe EDM experiment. We studied the optimum cell temperature and pumping laser power to improve the degree of Xe spin polarization. The best performance was achieved at the cell temperature of 100 C with the presently available laser power of 1 W. The results show that a more intense laser is required for further improvement of the spin polarization at higher cell temperatures in our experiment. [ABSTRACT FROM AUTHOR]