Akademik Məlumat İdarəetmə Sistemi
Physica Status Solidi (A) Applied Research, vol.198, no.2, pp.478-486, 2003 (Scopus)
The CaGa2S4 and SrGa2S4 with various grain sizes were studied over a wide range of photon energies at and below energy gap by using a spectroscopic phase modulated ellipsometer at room temperature. Complimentary, SEM and XRD techniques were applied. The pseudo-dielectric function of the samples with large grain sizes as compared to the light wavelength was found to be fairly reasonable. The energy gap for direct transitions in CaGa2S4 was estimated at ∼4.10eV. For samples with small grain sizes (∼100 nm), a splitting between principle angle and angle of minimal elliptic ratio, that could not be assigned to absorption was observed in the transient spectral range between diffraction and geometric optics.