Optoelectronic integrated device with light amplification and optical bistability

With the use of InP compound and InGaAsP alloy semiconductors, integrated devices have been fabricated in which a double heterojunction light-emitting diode is integrated onto the collector portion of a heterojunction phototransistor. The following results have been achieved in experiments with 1.15-µm wavelength light. The device amplifies the light. The maximum gain was 11.2 and the maximum differential was 31. The device is optically bistable. The optical bistability with positive gain was operated with at most 40-µW input light. The device exhibits a function similar to a light-activated thyristor and possesses a light unidirectional function. The unidirectionality measured was 16.5 dB.