Surface States and the Photoelectron-Spin Polarization of Ni(100)

High-resolution angle-resolved photoelectron emission spectra for Ni(100) are reported which identify a magnetic surface state just below the Fermi level. This surface state exists throughout the surface Brillouin zone including the zone-center Γ where its room-temperature binding energy and intrinsic width are 0.11 and 0.15 eV, respectively. These new results provide additional insight into the long-standing electron-spin polarization-sign-reversal controversy.