Multiphonon Absorption in the Chalcogenide Glasses As2S3 and GeS2
Semiconducting chalcogenide glasses generally exhibit a series of well defined multiphonon absorption peaks in the frequency region between about 400 and 4000 cm−1. Measurements of the frequency and temperature dependences of the one-phonon and multiphonon spectra in crystalline and glassy As2S3 and glassy GeS2 are compared with the predictions of a model calculation in which the anharmonic effects are approximated by a Morse potential. These calculations indicate that anharmonic contributions caused by nonlinearities in the dipole moment are significant in some chalcogenide glasses.
KeywordsChalcogenide Glass Morse Potential Alkali Halide Impurity Mode Band Edge Absorption
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