Real-space Green's function approach to angle-resolved resonant photoemission: Spin polarization and circular dichroism in itinerant magnets

Article

关键词: CORE-LEVEL PHOTOEMISSION;    ANGULAR-DISTRIBUTION;    HOLE POLARIZATION;    PERPENDICULAR GEOMETRY;    CONTINUOUS ABSORPTION;    SCATTERING APPROACH;    RAMAN-SCATTERING;    VALENCE STATES;    T-C;    PHOTOELECTRONS;   

DOI  :  10.1103/PhysRevB.88.115121

来源: SCIE

【 摘 要 】

A first-principles approach, based on the real-space multiple scattering Green's function method, is presented for spin-and angle-resolved resonant photoemission from magnetic surfaces. It is applied to the Fe(010) valence band photoemission excited with circularly polarized x rays around the Fe L-3 absorption edge. When the photon energy is swept through the Fe 2p-3d resonance, the valence band spectra are strongly modified in terms of absolute and relative peak intensities, degree of spin polarization, and light polarization dependence. New peaks in the spin-polarized spectra are identified as spin-flip transitions induced by exchange decay of spin-mixed core holes. By comparison with single-atom and band-structure data, it is shown that both intra-atomic and multiple scattering effects strongly influence the spectra. We show how the different features linked to states of different orbital symmetry in the d band are differently enhanced by the resonant effect. The appearance and origin of circular dichroism and spin polarization are analyzed for different geometries of light incidence and electron emission direction, providing guidelines for future experiments.

【 授权许可】

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