Spatial hysteresis and switching waves in thin-film semiconductor interferometers

An experimental investigation was made of the transformation of the intensity profile of a spatially confined light beam transmitted by optical bistable devices based on thin-film semiconductor interferometers formed by vacuum evaporation. A hysteresis of the intensity profile and switching waves was observed: these waves represented the process of consecutive transition from one stable state to another in neighboring zones of the interferometer. An experimental investigation was made of the velocity of switching waves in thin-film interferometers and in a model interferometer with a thermal nonlinearity.