Angle resolved photoemission spectroscopy of the InP(001) surface

The P-rich (2X1)/(2X2) and the In-rich (2X4) reconstructions of InP(001) are studied by Angle Resolved Photoemission Spectroscopy (ARPES). Experimental results for the In-rich (2 X 4) InP(001) surface show two bound surface states and one surface resonance, located at - 1.6 eV binding energy. This agrees well with ab-initio calculations. For the P-rich (2 X 1)/(2 X 2) lnP(001) surface, neither theoretical nor experimental work regarding the electronic surface structure exists until now. We identify two possible surface states showing no discernible dispersion along the <(Gamma)over bar>-(J) over bar and <(Gamma)over bar>-(J) over bar' directions of the surface Brillouin zone (SBZ), The energetically highest state, located close to the valence band maximum (VBM), is only observed along the [(1) over bar 10] direction and is most likely a P-dimer-bond state. The second state, located at - 4.4 eV binding energy, is assigned to a surface resonance. (C) 2000 Elsevier Science B.V. All rights reserved.