Angle-resolved photoelectron spectroscopy study of the InP(100)-(2x4) surface electronic structure

The InP(100)-(2 x 4) surface electronic structure was studied using angle-resolved photoelectron spectroscopy together with synchrotron radiation. We identify three surface states occurring in the gaps of the projected bulk bands. The highest level state, located at binding energy E-B = 1.0 eV, is consistent with previous findings. The second and third states, located at E-B = 1.8 and 4.3 eV, have not been reported previously. All three of these surface states show no discernible dispersion as compared to the surface states on InAs(100)-(2x4) and GaAs(100)-(2x4). This result suggests that the elements of the InP(100)-(2x4) surface unit cells are more isolated from each other than they are for the InAs(100)-(2x4) or the GaAs(100)-(2x4) surface.