Excitonic signatures in the photoluminescence and terahertz absorption of a GaAs/AlxGa1–xAs multiple quantum well
Galbraith, I., Chari, R., Pellegrini, S., Phillips, P. J., Dent, C. J., van der Meer, A. F. G., Clarke, D. G., Kar, A. K., Buller, G. S., Pidgeon, C. R., Murdin, B. N., Allam, J. and Strasser, G. (2005) Excitonic signatures in the photoluminescence and terahertz absorption of a GaAs/AlxGa1–xAs multiple quantum well Physical Review B, 71 (073302).
Measurements of the THz absorption and the time-resolved photoluminescence have been performed on the same GaAs quantum well sample. The strength of the absorption at the internal 1s-2p exciton transition frequency is used as a measure of the density of excitons in the sample. When the interband pump laser is resonant with the 1s exciton frequency, induced absorption at the s-2p frequency is clearly seen. If the same density of carriers is created pumping in the continuum, no significant 1s-2p absorption is seen in a time window of 450 ps. Complementary time-resolved photoluminescence experiments, detecting the emission at the exciton energy under the same pump conditions, show the PL intensity in resonant and nonresonant cases to be similar. The counter-intuitive existence of luminescence at the exciton energy simultaneously with the absence of the s-2p absorption is consistent with the recent theoretical predictions of Kira et al., Phys. Rev. Lett. 81, 3263 (1998).
|Divisions :||Faculty of Engineering and Physical Sciences > Electronic Engineering > Advanced Technology Institute > Photonics
Faculty of Engineering and Physical Sciences > Physics
|Date :||10 February 2005|
|Identification Number :||10.1103/PhysRevB.71.073302|
|Additional Information :||Published in Physical Review B, 71, 073302 (2005). © 2005 The American Physical Society.|
|Depositing User :||Mr Adam Field|
|Date Deposited :||27 May 2010 14:44|
|Last Modified :||23 Sep 2013 18:34|
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