Exciton front propagation in photoexcited GaAs quantum wells
نویسندگان
چکیده
Sen Yang,1 L. V. Butov,1 L. S. Levitov,2 B. D. Simons,3 and A. C. Gossard4 1Department of Physics, University of California at San Diego, La Jolla, California 92093-0319, USA 2Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA 3Cavendish Laboratory, Madingley Road, Cambridge CB3 OHE, United Kingdom 4Materials Department, University of California at Santa Barbara, Santa Barbara, California 93106-5050, USA Received 20 August 2009; revised manuscript received 10 February 2010; published 16 March 2010
منابع مشابه
Interferences and coherent control of excitons in GaAs quantum wells
Coherent control and light–heavy-hole beats observed in transient optical experiments in GaAs quantum wells are discussed in terms of a free-boson model. The properties of the exactly calculated wavefunction of the photoexcited system lead to a reinterpretation of the beats as due to classical electromagnetic interference, in contrast to the widely used quantum description based on few-level re...
متن کاملTunneling competition of photoexcited carriers in a system of monolithically integrated dual multiple InGaAs/AlGaAs and GaAs/AlGaAs quantum wells
Vertical transport of photoexcited carriers has been studied in a p-i-n diode whose intrinsic layer contains two different multiple quantum wells (MQW), GaAs/Al0.15Ga0.85As (MQW1) and strained In0.15Ga0.85As/Al0.15Ga0.85As (MQW2) isolated by a thick Al0.15Ga0.85As barrier. Pseudo-negative photocurrent (PC) peaks are observed at exciton resonance wavelengths of MQW1 located far from the n-electr...
متن کاملStimulated scattering of indirect excitons in coupled quantum wells: signature of a degenerate Bose-gas of excitons.
We observe and analyze strongly nonlinear photoluminescence kinetics of indirect excitons in GaAs/AlGaAs coupled quantum wells at low bath temperatures, > or = 50 mK. The long recombination lifetime of indirect excitons promotes accumulation of these Bose particles in the lowest energy states and allows the photoexcited excitons to cool down to temperatures where the dilute 2D gas of indirect e...
متن کاملNonparabolic band effects in GaAs/AlxGa1−xAs quantum dots and ultrathin quantum wells
We have investigated the optical properties of unstrained GaAs/AlxGa1−xAs quantum dot/well systems with the aim of studying the influence of confinement on the effective exciton mass, as determined from the photoluminescence line shift in high magnetic fields 50 T . The effective exciton mass is found to be more than twice the value for bulk GaAs. We attribute this to an enhanced nonparabolicit...
متن کاملFano profile in the intersubband terahertz response of photoexcited GaAs/AlGaAs quantum wells
In our work we probe the conduction intersubband transition of an undoped GaAs/Al0.34Ga0.66As multiple quantum well via broadband terahertz pulses after resonant photoexcitation at the 1s heavy-hole exciton. The pump-induced change in the transmitted terahertz field shows a strong beating. In the frequency domain this results in an asymmetric Fano-like line shape for the intersubband resonance ...
متن کامل