Photo-optical devices by amorphous As-S waveguides

Principles and fabrications of photo-optical devices based on the photoinduced refractive index changes observed in amorphous chalcogenide films are described. In these devices, propagation of a light beam in optical waveguides constructed with amorphous As-S films is controlled with blue- (and red-) light illumination which can modify the refractive index of the films. The devices operate as single-throw or double-throw photo-optical switches, having switching times ranging between 20 ms and 2 s.