APPEARANCE AND REORIENTATION OF PHOTOINDUCED ANISOTROPY IN CHALCOGENIDE GLASSY FILMS

The kinetics of appearance and reorientation of photoinduced dichroism (a manifestation of photoinduced anisotropy) is studied in chalcogeni de glassy films by means of the polarization modulation technique. Two distinct processes are identified: creation of photoinduced defects a nd photo-stimulated orientation of defects both native and photoinduce d. Of these processes, the first one can be carried out by both unpola rized and polarized radiation and has much larger time constant than t he second. The annealing temperatures of the two effects are also diff erent. In all of materials studied (AsSe, Ge2Pb1S4, Se) the effect of photoinduced anisotropy was shown to be a one-photon process. Unusual behavior of dichroism in partially crystallized Se films is revealed.