Nanoscaled chalcogenide films for optical applications.

Chalcogenide glasses from the [Ge(Te/Se)₅]_1-xInx system with 5,10,15,20,25 mol % In have been investigated. The composition trends of the glassy properties are discussed with the view of structural transformation in the main matrix. The optical spectra of the films have been studied to understand the role of indium on the film behavior. An optical characterization method, based on the transmission and the reflection spectra at normal incidence of uniform, thin films, has been used to obtain the thicknesses and optical constants corresponding to the as-deposited and annealed samples. The dispersion of the refractive index is discussed in terms of the single-oscillator Wemple-Di Domenico (WDD) model. The variations in the refractive index, the band gap, and the oscillation energy of the films after annealing are discussed with respect to rearrangement of the main structure units. [ABSTRACT FROM AUTHOR]