Angle-resolved photoelectron spectroscopy study of the InP(100)-(2×4) surface electronic structure

The $\mathrm{InP}(100)\ensuremath{-}(2\ifmmode\times\else\texttimes\fi{}4)$ 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 ${E}_{B}=1.0\mathrm{eV},$ 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 $\mathrm{InAs}(100)\ensuremath{-}(2\ifmmode\times\else\texttimes\fi{}4)$ and $\mathrm{GaAs}(100)\ensuremath{-}(2\ifmmode\times\else\texttimes\fi{}4).$ This result suggests that the elements of the $\mathrm{InP}(100)\ensuremath{-}(2\ifmmode\times\else\texttimes\fi{}4)$ surface unit cells are more isolated from each other than they are for the $\mathrm{InAs}(100)\ensuremath{-}(2\ifmmode\times\else\texttimes\fi{}4)$ or the $\mathrm{GaAs}(100)\ensuremath{-}(2\ifmmode\times\else\texttimes\fi{}4)$ surface.