Abstract: An efficient ripple free wide-band single-phase unidirectional SAW transducer is disclosed which requires only a single tuning circuit and a single matching circuit. The unidirectional transducer includes a pair of bidirectional transducers the first of which is connected to a single-phase drive source and the second is connected to a resonant load such that the second transducer acts as a reflecting transducer to cancel out waves traveling in one direction.

Abstract: An acousto-optic modulator is described which comprises a first support layer and a second layer of piezoelectric semiconductor material disposed over the support layer. The second layer includes a plurality of active sublayers, each active sublayer having a planar surface and thickness dimension which is such as to enable the active layer to exhibit quantum-well effects. A surface acoustic wave structure is disposed on the second layer for creating an acoustic wave in the second layer. The acoustic wave induces electric field variations therein which are perpendicular to the planar surface of the active sublayers and alter an optical property thereof. An optical beam is directed through the second layer, which beam is modulated by the altered optical properties of the active sublayers.