Photoinduced surface deformations in ion-conducting Ag-As-S glasses. II. Anisotropic deformation produced by large light spots

Anisotropic surface deformations appear in AgAsS2 chalcogenide films when exposed to linearly polarized 2.0 eV light spots with diameters of 5-200 mum. The anisotropic shape reflects the polarization direction. The shape also changes with the direction of light incidence. Illumination on the free surface of the films gives a craterlike deformation, and illumination through a substrate gives an anticrater deformation. In bulk samples, under any exposure conditions, an isotropic convex structure appears. The formation mechanisms of these patterns are discussed taking into account the photoinduced migration of Ag+ ions. (C) 2001 American Institute of Physics.