Tung C.-TLin H.-YChang S.-WCHAO-HSIN WU2022-04-252022-04-2520221077260Xhttps://www.scopus.com/inward/record.uri?eid=2-s2.0-85111765243&doi=10.1109%2fJSTQE.2021.3090527&partnerID=40&md5=29ae1b842b6427e191023114ddf0c4a0https://scholars.lib.ntu.edu.tw/handle/123456789/606956Compared with transistor lasers (TLs), tunnel-junction transistor lasers (TJTLs) are more easily modulated with the voltage across base-collector (BC) junction. In this work, the charge-control model and modified rate equation of TJTLs which includes the Franz-Keldysh effect and direct tunneling is developed. We conduct DC and AC analysis with our model and show that the doping concentration in the BC junction plays a key role in the capability to voltage modulate TJTLs since it affects the junction field. A trade-off between the optical power and capability of the voltage modulation emerges as a concern for designing the doping concentration. We also study the effect of the quantum well (QW) position. The result shows that the QW closer to the BC junction can obtain a higher confinement factor to achieve better output power and modulation bandwidth. ? 1995-2012 IEEE.Franz-Keldysh effectOptical frequency responseTransistor laserTunnel-junction transistor laserEconomic and social effectsModulationQuantum well lasersSemiconductor quantum wellsTransistorsCharge control modelConfinement factorDirect tunnelingDoping concentrationModulation bandwidthTransistor lasersVoltage modulationsTunnel junctions[SDGs]SDG7journal article10.1109/JSTQE.2021.30905272-s2.0-85111765243