We apply an interband pump/intersubband probe technique to monitor the temporal evolution of the electron population in the first and second subband of an undoped GaAs/AlGaAs asymmetric double quantum well after interband optical excitation. The spacing between the two subbands is smaller than the longitudinal optical phonon energy. The time dependence of the intersubband absorption can be explained by a simple rate equation model. We extract an intersubband lifetime of T21=100 ps and a recombination time of τ=410 ps at an excitation density of nS=2×1011 cm−2.

1.
J.
Faist
,
F.
Capasso
,
D. L.
Sivco
,
C.
Sirtori
,
A. L.
Hutchinson
, and
A. Y.
Cho
,
Science
264
,
553
(
1994
).
Google Scholar
 
2.
B. F.
Levine
,
J. Appl. Phys.
74
,
R1
(
1993
).
Google Scholar
 
3.
P.
Boucaud
,
F. H.
Julien
,
D. D.
Yang
,
J. M.
Lourtioz
,
E.
Rosencher
,
P.
Bois
, and
J.
Nagle
,
Appl. Phys. Lett.
57
,
215
(
1990
).
Google Scholar
 
4.
J.
Faist
,
F.
Capasso
,
C.
Sirtori
,
D. L.
Sivco
,
A. L.
Hutchinson
,
S. N. G.
Chu
, and
A. Y.
Cho
,
Appl. Phys. Lett.
63
,
1354
(
1993
).
Google Scholar
 
5.
R.
Ferreira
and
G.
Bastard
,
Phys. Rev. B
40
,
1074
(
1989
).
Google Scholar
 
6.
K.
Craig
,
C. L.
Felix
,
J. N.
Heyman
,
A. G.
Markelz
,
M. S.
Sherwin
,
K. L.
Campman
,
P. F.
Hopkins
, and
A. C.
Gossard
,
Phys. Rev. Lett.
76
,
2382
(
1996
).
Google Scholar
 
7.
K.
Craig
,
C. L.
Felix
,
J. N.
Heyman
,
A. G.
Markelz
,
M. S.
Sherwin
,
K. L.
Campman
,
P. F.
Hopkins
, and
A. C.
Gossard
,
Semicond. Sci. Technol.
9
,
627
(
1994
).
Google Scholar
 
8.
J. N.
Heyman
,
K.
Unterrainer
,
K.
Craig
,
B.
Galdrikian
,
M. S.
Sherwin
,
K.
Campman
,
P. F.
Hopkins
, and
A. C.
Gossard
,
Phys. Rev. Lett.
74
,
2682
(
1995
).
Google Scholar
 
9.
B. N.
Murdin
,
W.
Heiss
,
C. J. G. M.
Langerak
,
S.-C.
Lee
,
I.
Galbraith
,
G.
Strasser
,
E.
Gornik
,
M.
Helm
, and
C. R.
Pidgeon
,
Phys. Rev. B
55
,
5171
(
1997
).
Google Scholar
 
10.
J. N.
Heyman
,
K.
Unterrainer
,
K.
Craig
,
J.
Williams
,
M. S.
Sherwin
,
K.
Campman
,
P. F.
Hopkins
,
A. C.
Gossard
,
B. N.
Murdin
, and
C. J. G. M.
Langerak
,
Appl. Phys. Lett.
68
,
3019
(
1996
).
Google Scholar
 
11.
J.
Faist
,
C.
Sirtori
,
F.
Capasso
,
L.
Pfeiffer
, and
K. W.
West
,
Appl. Phys. Lett.
64
,
872
(
1994
).
Google Scholar
 
12.
M. C.
Tatham
,
J. F.
Ryan
, and
C. T.
Foxon
,
Phys. Rev. Lett.
63
,
1637
(
1989
).
Google Scholar
 
13.
D. Y.
Oberli
,
D. R.
Wake
,
M. V.
Klein
,
J.
Klem
,
T.
Henderson
, and
H.
Morkoç
,
Phys. Rev. Lett.
59
,
696
(
1987
).
Google Scholar
 
14.
M.
Hartig
,
S.
Haacke
,
P. E.
Selbmann
,
B.
Deveaud
,
R. A.
Taylor
, and
L.
Rota
,
Phys. Rev. Lett.
80
,
1940
(
1998
).
Google Scholar
 
15.
J. A.
Levenson
,
G.
Dolique
,
J. L.
Oudar
, and
I.
Abram
,
Phys. Rev. B
41
,
3688
(
1990
).
Google Scholar
 
16.
K.
Požela
,
S. B.
Naran
,
J.-P.
Leburton
, and
J. N.
Heyman
,
Appl. Phys. Lett.
77
,
265
(
2000
).
Google Scholar
 
17.
S.
Sauvage
,
P.
Boucaud
,
F. H.
Julien
,
O.
Gauthier-Lafaye
,
V.
Berger
, and
J.
Nagle
,
Appl. Phys. Lett.
71
,
1183
(
1997
).
Google Scholar
 
18.
R. A.
Kaindl
,
D. C.
Smith
, and
T.
Elsaesser
,
Opt. Lett.
23
,
861
(
1998
).
Google Scholar
 
19.
M.
Joffre
,
A.
Bonvalet
,
A.
Migus
, and
J.-L.
Martin
,
Opt. Lett.
21
,
964
(
1996
).
Google Scholar
 
20.
K.
Kempa
,
P.
Bakshi
,
J.
Engelbrecht
, and
Y.
Zhou
,
Phys. Rev. B
61
,
11083
(
2000
).
Google Scholar
 
This content is only available via PDF.
© 2001 American Institute of Physics.
2001
American Institute of Physics
You do not currently have access to this content.