OPTICAL-PROPERTIES OF SB-TERMINATED GAAS AND INP(110) SURFACES

The dielectric function and the Raman scattering cross section for surface vibrations on InP and GaAs (110) surfaces terminated with an antimony monolayer were calculated using the empirical tight-binding method. The calculations reproduce well the surface dielectric function and its anisotropy. The Raman cross section for surface vibrations was determined for deformation-potential-induced scattering by calculating the changes in the dielectric function caused by the surface phonon eigenmodes. In agreement with the experimental results, the different surface phonon modes exhibit different resonance profiles since the coupling to the surface electronic states strongly depends on the respective atomic displacements. The results demonstrate that, as for the bulk case, resonant Raman scattering can be used to probe the surface electronic properties.