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We have performed x-ray magnetic circular dichroism experiments to study the cancellation of spin and orbital magnetic moments in ͑Sm, Gd͒Al 2 , a ferromagnet without net magnetization at a certain compensation temperature, T comp. We verified the existence of long-range order for both spin and orbital magnetic moments at T comp. The spin and orbital magnetic moments of the Sm ion are found always antiparallel coupled and the magnitude of its orbital magnetic moment is always larger than that of spin one, so the cancellation of magnetic moments cannot be achieved by only Sm 4f electrons. We show that the addition of spin magnetic moments of Gd ions and conduction electrons, which are ferromagnetically coupled with the spin magnetic moment of Sm ions, cancels out the surplus orbital magnetic moments in Sm ions completely and results in the zero magnetization at T comp. All our experimental results can be reproduced well by atomic multiplet calculations.

Absolute spin calibration of an electron spin polarimeter by spin-resolved photoemission from the Au(111) surface states Rev. Sci. Instrum. 80, 043904 (2009); A new compact 60 kV Mott polarimeter for spin polarized electron spectroscopy Rev.

We have observed the site-resolved (Co, Mn and Ge) magnetic moments of Co2MnGe with the use of 2p core absorption spectroscopy (XAS) and x-ray magnetic circular dichroism (XMCD). The evaluated Co and Mn 3d spin magnetic moments are consistent with the values given by the neutron scattering experiment. We have found that the orbital magnetic moment is large for the Co 3d states and is recognizable even for the Mn 3d state, suggesting that a spin–orbit coupling should be reconsidered in the energy band structure in order to verify a half-metallic nature of this alloy. Moreover, we have revealed that the magnetic moment is induced on the Ge site in Co2MnGe.

Spin-and angle-resolved photoemission spectroscopy has been applied to the study on spin polarized electronic structures of fct Co thin film with thicknesses from 2 ML to 9.5 ML. We have clearly observed two dispersive majority and minority spin band structures originating from the bulk-like bands. These observed band structures show narrower width for thinner film due to an in-plane lattice expansion at the Co-Cu interface.