Non-linear Raman effects and photodarkening in chalcogenide glass

¹ Laboratoire de Spectrochimie Infrarouge et Raman (CNRS, UMR 8516), Bât. C-5 Centre d'Etudes et de Recherches Lasers et Applications (CERLA-FR CNRS 2416) Université des Sciences et Technologies de Lille - 59655 Villeneuve d'Ascq, France and
² Laboratoire de Physique des Lasers, Atomes et Molécules (CNRS, UMR 8523), Bât. P-5, Centre d'Etudes et de Recherches Lasers et Applications (CERLA-FR CNRS 2416) Université des Sciences et Technologies de Lille - 59655 Villeneuve d'Ascq, France
³ Novel Photonic Glasses Research Group, Wolfson Building, University of Nottingham Nottingham NG7 2RD, UK
⁴ Institute for High Physical Technology - Jena, Germany

Corresponding author: Sylvia.Turrell@univ-lille1.fr

Received: 3 February 2006
Accepted: 1 September 2006

Abstract

The intensities of Raman-scattering bands in the spectrum of vitreous assigned to vibrations of intrinsic homopolar As-As () and S-S () bonds increase much more with the power of the exciting laser than does the principle vibrational band which is related to As-S-As glass-network vibrations (). In addition, the frequency of this glass-network vibration softens with an increase of the laser power. We ascribe these non-linear Raman effects to a photo-stimulated increase in polarizability of the homopolar bonds accompanied by softening of glass-network vibrations. It is suggested that this non-linearity is related to photodarkening in .