Integration of a GaAs/AlGaAs all-optical switch with disordered branching waveguides

Multiple quantum well (MQW) structures have attractive electro-optic and nonlinear properties at optical frequencies close to the band-gap frequency. All-optical waveguide switching devices fabricated from MQW materials have previously been demonstrated. In this paper, we present the use of area-selective disordering of GaAs-AlGaAs MQW structures in order to realize integrated optics devices and bring us closer to the realization of integrated optical circuits. One of the devices that will be described is an all-optical X-switch that is fabricated in a MQW layer that has been disordered everywhere except for the central region of the X-switch. The device is basically a zero-gap nonlinear directional coupler with branching waveguides. The use of disordered branching waveguides results in low coupling losses.