Discrepancies between photocurrent and absorption spectroscopies in intersubband photoionization from GaAs/AlGaAs multiquantum wells
- 16 December 1991
- journal article
- Published by AIP Publishing in Applied Physics Letters
- Vol. 59 (25) , 3255-3257
- https://doi.org/10.1063/1.105749
Abstract
Intersubband transitions between a bound state and extended states in GaAs/AlGaAs multiquantum wells are studied by simultaneous absorption and photocurrent spectroscopy under different electric field conditions. It is found that both types of spectra exhibit different line shapes, with the photocurrent maximum occurring at lower photon energy than in absorption spectra. Moreover, there is a blue shift of absorption peak and a red shift of photocurrent peak with increasing electric fields. These results suggest that a sequential mechanism is involved in the photocurrent collection from the quantum well. The blue shift is then well fitted by a quadratic Stark effect and the red shift by a barrier lowering mechanism.Keywords
This publication has 8 references indexed in Scilit:
- Direct determination of the electron-tunneling escape time from a GaAs/As quantum well by transient-capacitance spectroscopyPhysical Review B, 1991
- Intersubband photocurrent from the quantum well of an asymmetrical double-barrier structureJournal of Applied Physics, 1991
- Bound-free intraband absorption in GaAs-AlxGa1−xAs semiconductor quantum wellsApplied Physics Letters, 1989
- Tunneling lifetime broadening of the quantum well intersubband photoconductivity spectrumApplied Physics Letters, 1988
- New 10 μm infrared detector using intersubband absorption in resonant tunneling GaAlAs superlatticesApplied Physics Letters, 1987
- Observation of Stark shifts in quantum well intersubband transitionsApplied Physics Letters, 1987
- First observation of an extremely large-dipole infrared transition within the conduction band of a GaAs quantum wellApplied Physics Letters, 1985
- New mode of IR detection using quantum wellsApplied Physics Letters, 1984