TITLE

Time constant for relaxation of n=2 excitons into n=1 continuum states in GaAs quantum wells

AUTHOR(S)
Pal, Bipul; Vengurlekar, A. S.
PUB. DATE
July 2001
SOURCE
Applied Physics Letters;7/2/2001, Vol. 79 Issue 1, p72
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
We resonantly excite excitons associated with the second electron and heavy hole subbands (n=2 excitons) in 13 and 17.5 nm GaAs quantum wells (QWs) at 8 K to perform femtosecond degenerate four wave mixing measurements. We deduce the lifetime T[sub 1] of the n=2 excitons to be approx. 890 fs and approx. 2.63 ps, respectively, for the 13 and 17.5 nm QWs. © 2001 American Institute of Physics.
ACCESSION #
4710048

 

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