Unoccupied surface state and conduction band critical points of GaP(110): A high resolution inverse photoemission study

Abstract
We report the first angle-resolved, high-resolution inverse photoemission study of the cleaved (110) surface of GaP. The experiment was performed at normal electron incidence for electron energies between 11.6 and 18.6 eV. We are able to resolve the unoccupied dangling bond surface state in the band gap of GaP at 0.3 eV below the conduction band minimum. The maximum of the Γ1 X1 band is found at about 4.5 eV.