ELECTRONIC BAND-STRUCTURE OF MONOLAYER SB ON GAP(110)

We have used angle resolved ultra violet photoelectron spectroscopy (ARUPS) with synchrotron radiation to map the two dimensional electronic bandstructure of monolayer Sb on GaP(110). The dispersion of the features in the valence band was followed along the four symmetry directions of the surface Brillouin zone using sets of spectra taken at several photon energies. Five bands originating from surface states were then identified and selection rules based on polarisation and emission geometry were used to probe the nature of these states. The experimental results are compared with recent tight-binding and pseudopotential calculations for Sb/GaP(110).