Layer-dependent band dispersion and correlations using tunable soft X-ray ARPESN. Kamakura1, Y. Takata1, T. Tokushima1, Y. Harada1, A. Chainani1, 2, K. Kobayashi3 and S. Shin1, 4
1 RIKEN, Harima Institute - 1-1-1 Kouto, Mikazuki, Sayo, Hyogo 679-5148, Japan
2 Institute for Plasma Research - Bhat, Gandhinagar 382 428, Gujarat, India
3 SPring-8/JASRI - Mikazuki, Hyogo 679-5198, Japan
4 Institute for Solid State Physics, University of Tokyo Kashiwanoha, Kashiwa, Chiba 277-8581, Japan
(Received 22 January 2004; accepted in final form 3 May 2004)
Soft X-ray Angle-Resolved Photoemission Spectroscopy is applied to study in-plane band dispersions of nickel as a function of probing depth. Photon energies between and 780 were used to effectively probe up to -7 layers ( -12 ). The results show layer-dependent band dispersion of the minority spin band which crosses the Fermi level in 3 or more layers, in contrast to the known top 1-2 layers dispersion obtained using ultra-violet rays. The layer dependence corresponds to an increased value of exchange splitting and suggests reduced-correlation effects in the bulk compared to the surface.
71.20.Be - Transition metals and alloys.
79.60.-i - Photoemission and photoelectron spectra.
75.50.Cc - Other ferromagnetic metals and alloys.
© EDP Sciences 2004