A series of alkali halide doped chalcohalide glasses (100-x)(0.9GeS2-0.1Sb2S3)-xCsCl (x=5, 10, 15 and 20 mole fraction) were prepared. The absorption spectra and Raman scatting spectra of these glasses were measured. The optical band gaps Eopt were obtained from ultraviolet absorption edges. Z-scan technique was utilized to investigate the third-order nonlinear optical properties of GeS2-Sb2S3-CsCl glasses. The value of Eopt increases and the third-order optical nonlinearity decreases with increasing CsCl content. Decreasing lone-pair electron and broadening the band-gap will provide less transition paths for nonlinear process, which play a key role in ultrafast third-order nonlinear optical responses of these chalcohalide glasses.
The kinetics of crystallization in 70GeS2-20Sb2S3-10CsCl chalcogenide glass was studied using differential scanning calorimetry (DSC) at different heating rate. The values of glass transition and crystallization temperatures were found to be heating rate dependent. Using Matusita method, the crystallization activation energies E and crystallization parameter (n) calculated are 348.08±0.99 kJ/mol and 1.78. It suggests that there are two mechanisms: a surface and one-dimensional crystallization processes.