Highly compact integrated optical set-reset memory pixels for parallel processing arrays

An integrated optoelectronic device with a single-mesa structure, which functions as an optical set-reset memory or an optical inverter, is reported. The device is composed of two heterojunction phototransistors and a light-emitting diode vertically integrated on an InGaAsP/InGaAs/InP wafer grown by gas source molecular beam epitaxy. The set and reset beams are incident on a single optical window on each device and are separated by wavelength. The prototype device has shown a large on/off control ratio (27) with relatively low input optical power levels (tens of microwatts). This device concept is extendable to large integrated arrays which are capable of directly processing spatial light signals.<
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