Surface electronic structure of Fe(110): the importance of surface resonances

Thick Fe(1 1 0) films (>50 ML) have been epitaxially grown on W(1 1 0) and studied by spin- and angle-resolved photoemission spectroscopy utilizing linearly polarized synchrotron radiation. The photoemission spectra display two surface sensitive 3d-derived features. The first, located at Γ, consists of an exchange-split pair (Δex=2.3 eV) with a sharp minority peak at about 0.25 eV below EF and a broader majority counterpart; the second, located midway along the Γ–S symmetry line of the surface Brillouin zone, is a majority peak close to EF. A comparison of the experimental results with first-principle slab calculations reveals that both features are surface resonances, with a substantial charge density distribution on both the surface and the subsurface Fe(1 1 0) layer.