THERMAL AND OPTICAL STUDY OF TE15(SE100-XBIX)(85) (X = 0, 1, 3) CHALCOGENIDE GLASSES

The present paper reports the thermal and optical study of Te-15( Se100-xBix)(85) (x 0, 1, 3 at. %) glassy alloys. The glass transition temperature (T-g), crystallization temperature (T-c) and melting temperature (T-m) are found from the DTA plots taken at different heating rates of 10, 15, 20 and 25 K/min. The glass transition temperature and melting temperature have been found to increase and the crystallization temperature has been found to decrease with increase in Bi content (x). Refractive index and optical energy gap of the films have been calculated from the transmission spectra taken in the spectral range 400-2300 nm. The refractive index decreases with wavelength and the optical band gap decreases with increase in Bi content.