Abstract
The operation characteristics of optically controlled three-terminal gates consisting of a multiple quantum well (MQW) reflection modulator and a heterojunction phototransistor (HPT) are discussed. It is found that the photonic gates, in which both components are electrically connected in series and parallel, operate as NOR and OR gates, respectively. The photonic gates exhibit a high contrast ratio of more than 20 dB as well as optical gain.<>