The Monolithic Optoelectronic Transistor

We report a new smart-pixel device, the monolithic optoelectronic transistor (MOET). It uses GaAs/AIGaAs multiple-quantum-well p-i-n diodes as both photodetectors for optical input and reflection modulators for optical output The switching action is obtained by using a double-barrier resonant-tunneling diode (RTD). The RTD is connected in series with the input detector and produces an abrupt voltage change at a threshold level of photocurrent This voltage change is amplified by a FET to drive the output modulator.