THE PHOTOLUMINESCENCE AND TRANSMITTANCE STYDY OF MECHANICAL AMORPHYZATION OF GeSe_2, As_2Se_3, As_2S_3 SINGLE CRYSTALS

摘要

Reversible photostructural conversions (darkening and bleaching) attended by a shift of transmittance edge and by the photoluminescence fatigue effect are revealed. Upon mechanical treatment of crystals the maximum, of the luminescence excitation spectrum shifts toward higher energies. The low-energy edge of the luminescence spectrum flattens, and emission intensity increases. The experimental results are interpreted within a configuration model of two stable structural states of molecular groups.