Berreman Effect in Amorphous and Crystalline WO3 Thin Films

摘要: Thin films of tungsten oxide deposited by hot filament metal deposition (HFMOD) were thermally annealed up to 800 °C and investigated means XRD, Raman spectroscopy, infrared reflection−absorption spectroscopy (IRRAS). As clearly shown the XRD data, amorphous crystallized thermal annealing. The monoclinic WO3 phase was formed in all samples. IRRAS spectra obtained using IR beam with p-polarization an off-normal incidence angle. In this condition, absorptions due longitudinal optical (LO) modes (Berreman effect) can be observed spectra. Absorptions LO are not detected standard absorption which unpolarized is used at normal incidence, thus frequently reported literature. To analyze experimental spectra, TO functions calculated from transmission as-deposited sample, Kr...