Polarization dependent photoemission from d-like surface states on Cu

Abstract

Using polarized He I (21.2 eV) and He II (40.8 eV) radiation, we have studied high-resolution angle-resolved photoemission from two very narrow surface states observed recently on Cu(100) and Cu(111) by Heimann et al. (Phys. Rev. B20 (1979) 3059). Our results clearly demonstrate, that both surface states have d-like orbital character, with odd reflection symmetry in their emission mirror planes, identical to the symmetry behaviour of the topmost bulk d bands. Our results strongly support the model, that these surface states are split off from the bulk bands by the surface potential.