Abstract

Arsenic chalcogenide glasses for IR fiber and data storage uses exhibit photoinduced structural transformations when irradiated by below-band- gap light. We demonstrate that these transformations are enhanced by irradiating at a self-trapped exciton (STE) resonance wavelength. Rayleigh and Raman signals show that STE decay leads to instabilities among metastable structural states in bulk glass. With time constants of the order of seconds, these instabilities may switch abruptly into states of increased order. By varying the relative concentration in these binary compounds, we control the availability of the initial STE forming state. These measurements provide evidence that photoinduced structural transformations in arsenic selenides occur at 1-5 W/cm² irradiation levels.

© 1991 Optical Society of America