GaAs/AlGaAs Single Quantum Well Optical Switch Fabricated on Si Substrate

We report a single-mode waveguide-type optical switch with a double hetero (DH)-structure fabricated on a Si substrate by Metalorganic Chemical Vapor Deposition (MOCVD). This switch utilizes the quantum confined Stark effect (QCSE). The sample consists of an Al0.3Ga0.7As cladding layers and Al0.25Ga0.75As guiding layer with an 8.3-nm-wide GaAs single quantum well (SQW). To measure the light absorption under reverse bias, the photo current method was applied out using a cw Ti:sapphire laser. We measured about a 10 nm shift of the absorption edge at - 8 V. This switch exhibits a 33. 1 dB/mm extinction ratio at 867 nm wavelength under - 8 V bias.