ORIGIN OF NEAR-INFRARED OPTICAL-DAMAGE ON PROUSTITE SURFACES

Optical damage induced by infrared irradiation of proustite is investi gated with holographic methods and photoelectron spectroscopy. Hologra phic writing results in thin absorption gratings located on the surfac e. This phenomenon is traced back to formation of Ag2S by a decomposit ion reaction on the surface of aged proustite crystals and generation of a metastable state of Ag2S by infrared light. The writing and erasi ng kinetics is studied by two-beam mixing with Nd3+-doped yttrium alum inium garnet laser radiation with lambda=1.06 mu m. The metastable abs orption gratings induced on the surface reach a diffraction efficiency of a few per cent and have a storage time of 10(4) s.