Polarization dependence of optical transitions in GaP(110) and GaAs(110) surfaces studied with surface differential reflectivity

We present results on the polarization dependence of Surface Differential Reflectivity in GaP(1 1 0) and GaAs(GaAs(1 1 0) surfaces. GaP(1 1 0) shows a transition at 2.8 eV which is excited only with the light electric vector parallel to the [1 1 0] direction; for the optical transition above 3.0 eV there is not any marked polarization dependence. GaAs(1 1 0) shows optical transitions between 2.6 and 4.0 eV which have a weak dependence on light polarization.