Electro-optic low-voltage InGaAs/GaAs multiple quantum well modulator with organic-inorganic distributed Bragg reflector

We have realized a reflection-type electro-optic InGaAs/GaAs multiple quantum well (MQW) modulator using an organic-inorganic distributed Bragg reflector (DBR). The MQW active layer is embedded in the intrinsic region of a p-i-n diode. The DBR consists of few pairs of CFx/TiOx layers, fabricated by room-temperature ion beam sputtering on the rear side of the device. The reflectivity of the mirror approaches 98% in the infrared spectral region and is centered at the n = 1 exciton resonance of the MQW. ON-OFF driving reverse voltages of 0.5 and 1.8 V are measured at room temperature. In this range the static response of the device is linear so that it can be used for analog electro-optic modulation. (C) 1999 Academic Press