HOLE TRANSPORT OVER HETEROBARRIERS IN INP BASED MULTIPLE-QUANTUM-WELLSTRUCTURES

We present a systematic analysis of the hole transport over heterobarr iers in the InGaAs(P)/InP material system. The experiments have been p erformed on our recently developed all-optical switching structures [C . Knorr et al., Appl. Phys. Lett. 69, 4212 (1996)], which offer an ele gant access to hole transport rates. We have varied barrier thickness, barrier height, bias voltage, and temperature. The time constants var y from 30 mu s to 30 ns. Our model calculations, including all heavy a nd light hole subbands, show that only thermally assisted tunneling ca n explain both the temperature and electric field dependence of the tr ansport rates. We have extracted the activation energies. The hole cap ture time is determined as 250 +/- 50 fs. (C) 1998 American Institute of Physics.