Occupied surface-state bands of Bi(1×1) overlayers on an InAs(110) surface grown by molecular-beam epitaxy

Abstract

The ordered p(1\ifmmode\times\else\texttimes\fi{}1) monolayer phase of Bi on InAs(110) has been studied with the technique of angle-resolved ultraviolet photoemission spectroscopy. Three Bi-induced surface-state bands (S',S'', and S''') have been observed. Their respective band dispersions have been mapped along the high-symmetry lines of the surface Brillouin zone. The upper two bands, S' and S'', appear to be degenerate across most of the surface Brillouin zone except along the \ensuremath{\Gamma}\ifmmode\bar\else\textasciimacron\fi{}-X\ifmmode\bar\else\textasciimacron\fi{}' symmetry line. The bandwidths of the Bi-induced states of Bi/InAs(110) are significantly narrower than that of Bi/GaAs(110) or Sb/GaAs(110). The polarization of these surface-state bands has been measured and compared to predictions of current theoretical models for Sb/GaAs(110).