Dynamic Characteristics of Photonic Gate with Multiple-Quantum-Well Reflection Modulator and Heterojunction Phototransistor

Abstract

Summary form only given. In order to improve the switching-off speed of a photonic gate array consisting of a multiple-quantum-well (MQW) modulator, a distributed Bragg reflector (DBR), and a heterojunction phototransistor (HPT), a resistor structure connected in parallel with the modulator is proposed. The bandwidth was measured as a function of the optical gain for the following two gate structures: the MQW reflection modulator connected with (1) the p-i-n photodiode in series; and (2) the HPT in series and the resistor in parallel, respectively. The results show that the addition of the resistor can reverse the increase in switching-off time due to the Miller capacitance effect with optical gain. Estimates indicate that optimizing the device size and structure will result in subnanosecond switching times with several times the optical gain. >