Bulk and Impurity Infrared Absorption in 0.5 As2Se3-0.5 GeSe2Glasses.

摘要

A study of infrared absorption in the 250 to 4000/cm region has been carried out for 0.5 As2Se3-0.5 GeSe2 glasses quantitatively doped with oxide impurity. The frequencies of the intrinsic 2- and 3-phonon absorption bands at 490 and 690/cm correspond well to those predicted from combinations of the high frequency bands in the first order IR and Raman spectra of As2Se3 and GeSe2 glasses. Glasses doped with As2O3 exhibit the same oxide impurity absorption bands as those doped with GeO2. Unlike As2Se3 glass, at impurity concentrations up to 100 ppm AS2O3, 0.5 As2Se3 - 0.5 GeSe2 glass exhibits only one major oxide impurity species, characterized by absorption bands at 780 and 1260/cm and due to oxygen bonded to network Ge. The observation of a much weaker network As-O vibration band at 670/cm confirms that oxygen bonds preferentially to Ge in this glass. The same minor oxide species appears to determine excess IR absorption at the CO2 laser wavelength of 10.6 micrometers in both As2Se3 and 0.5 As2Se3-0.5 GeSe2 glasses. The frequencies and intensities of absorption bands due to hydrogen impurities are also quite comparable for these two materials. (Author)