Optical transitions between surface states on cleaved CdTe(110)

Surface differential reflectivity measurements have been carried out for a cleaved CdTe(110) surface. A broad structure centered around 3.5 eV has been found and been deconvolved into three main spectral features at 2.9, 3.5, and 3.9 eV. Our analysis ascribes these peaks to optical transitions at the \ensuremath{\Gamma}, X, and X' points of the surface Brillouin zone, respectively. The oxidation process of the surface was analyzed and the sticking coefficient of excited molecular oxygen was estimated.