Emissionszeit von Ladungsträgern in GaAs/AlGaAs und InGaAs/GaAs Quantenfilmlasern

: Esquivias, I.; Romero, B.; Weisser, S.; Czotscher, K.; Ralston, J.D.; Larkins, E.C.; Arias, J.; Schönfelder, A.; Mikulla, M.; Fleissner, J.; Rosenzweig, J.

Abstract
The transport of carriers along the confinement region, the carrier capture into, and the carrier escape out of the quantum wells (QWs) are limiting processes affecting the high-frequency properties of QW lasers. The influence of these processes on the laser performance depends mainly on the ratio of the effective carrier transport/capture time and the effective escape time. We present experimental results about the escape times for GaAs/A1GaAs and InGaAs/GaAs high-speed QW lasers with varied geometrical dimensions (cavity width and length), number of QWs, In-concentrations, and p-doping levels in the active region, as extracted from electrical impedance measurements in the sub-threshold regime. In addition to the expected increase of the escape time with increasing QW barrier height, we observe an important increase in the escape time for lasers with p-doping. The escape time dependences on the carrier concentration and on the temperature are determined and discussed.