Abstract
Using far-infrared time-resolved spectroscopy, we have investigated the effect of quantum-well confinement on the lifetime of shallow acceptor states in GaAs/AlAs multiple quantum wells with Be δ-doping at the well center. Low-temperature far-infrared absorption measurements clearly show three principal absorption lines due to transitions of Be acceptor states from the ground state to the first three odd-parity excited states, respectively. It is found that the lifetime of excited states monotonically reduces with decreasing quantum-well width, from 350 ps in bulk to 55 ps in a 100 Å well. We suggest that the effect of quantum-well confinement on zone-fold acoustic-phonon modes increases the intra-acceptor scattering rate of acoustic-phonon-assisted relaxation.
Original language | English |
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Pages (from-to) | 3719-3721 |
Number of pages | 3 |
Journal | Applied Physics Letters |
Volume | 83 |
Issue number | 18 |
Early online date | 28 Oct 2003 |
DOIs | |
Publication status | Published - 3 Nov 2003 |
Externally published | Yes |