Photoinduced effect in glassy crystalline As4Se3:: Negative photoinduced anisotropy -: art. no. 104201

In studying the optical-transmission properties of the glassy crystalline chalcogenide composition As4Se3 with polarized light, we have observed a photoinduced phenomenon, called here negative vectoral photoinduced anisotropy. The negative anisotropy is ascribed to As4Se3 molecular units embedded in an amorphous network. During the course of illumination, the negative anisotropy gradually decreases in amplitude and is replaced by the well-known, previously observed positive vectoral anisotropy. A microscopic mechanism for the occurrence of negative anisotropy is suggested.