Photoluminescence (PL), PL excitation (PLE), and time-resolved PL are employed to study the tunneling of photoexcited holes through a GaAs/A1GaAs double-barrier resonant tunneling structure. Lifetime measurements of the n= 1 heavy-hole (hh) exciton transition from the well were obtained as a function of the applied voltage. For voltages biasing the structure in the non-resonant tunneling regime, beyond the region of negative differential resistance (NDR), the exciton decays with two time constants. The fast component, which was observed at all voltages, is attributed to the decay of the exciton population originating from holes photoexcited directly in the well. The slower time constant is associated with excitons that are created from hOles which are photoexcited in the GaAs contact region, and which subsequently tunnel into the well. This picture for hole tunneling is further supported by the observation of the n= 1 hh exciton emission using exciting photon energies lower than the quantum well bandgap but larger than the GaAs bandgap, when the structure is biased beyond the region of NDR.

Date Published: 1 October 1990
PDF: 12 pages
Proc. SPIE 1283, Quantum Well and Superlattice Physics III, (1 October 1990); doi: 10.1117/12.20725

Published in SPIE Proceedings Vol. 1283:
Quantum Well and Superlattice Physics III
Gottfried H. Doehler; Emil S. Koteles; Joel N. Schulman, Editor(s)