Ehret, S.S.EhretSchneider, H.H.SchneiderFleissner, J.J.FleissnerKoidl, P.P.KoidlBöhm, G.G.Böhm2022-03-032022-03-031997https://publica.fraunhofer.de/handle/publica/19145910.1063/1.119815We report on a high bandwidth measurement of the transient intersubband photocurrent of a GaAs/AlGaAs multiple quantum-well infrared photodetector (QWIP). The photocurrent is excited via tunable subpicosecond infrared pulses. The response time of the detector has a full width at half-maximum of 18.5 ps and a rise time of 14.5 ps, which is limited by the electrical circuit. The decay time of the photocurrent response exhibits a significant dependence on the applied voltage, with increasing decay times for increasing bias voltages. From the experimental data, we conclude that the intrinsic response time of a QWIP is less than 7 ps.enintersubband photocurrentIntersubband-PhotostromQWIPtime resolved photocurrentzeitaufgelöster Photostrom621667journal article