We have investigated terahertz (THz) emission due to dynamical electron transport in wide miniband GaAs/Al0.3Ga0.7As superlattices by time-resolved THz emission spectroscopy. Quasiautocorrelation measurements were performed on the emitted THz electromagnetic waves by using a bolometer as a wideband detector. The bias-field dependence of the emitted THz radiation intensity clearly showed a crossover from the miniband transport to the formation of Wannier–Stark ladder. In the Wannier–Stark regime, a few cycle Bloch oscillations were observed even at 300 K in a superlattice whose miniband width is greater than the longitudinal optical phonon energy. Furthermore, it has been found that clear Bloch oscillations are visible only when the bottom of the miniband is photoexcited.

Topics
Electronic transport, Bloch oscillation, Phonons, Superlattices, Terahertz radiation, Electromagnetic radiation detectors, Terahertz emission spectroscopy, Photoexcitations
1.
L.
Esaki
and
R.
Tsu
,
IBM J. Res. Dev.
14
,
61
(
1970
).
Google Scholar
 
2.
A.
Sibille
,
J. F.
Palmier
,
C.
Minot
, and
F.
Mollot
,
Appl. Phys. Lett.
54
,
165
(
1989
).
Google Scholar
 
3.
J.
Feldmann
,
K.
Leo
,
J.
Shah
,
D. A. B.
Miller
,
J. E.
Cunningham
,
T.
Meier
,
G. von
Plessen
,
A.
Schulze
,
P.
Thomas
, and
S.
Schmitt-Rink
,
Phys. Rev. B
46
,
7252
(
1992
).
Google Scholar
 
4.
K.
Leo
,
P. Haring
Bolivar
,
F.
Brüggemann
,
R.
Schwedler
, and
K.
Köhler
,
Solid State Commun.
84
,
943
(
1992
).
Google Scholar
 
5.
F.
Löser
,
Y. A.
Kosevich
,
K.
Köhler
, and
K.
Leo
,
Phys. Rev. B
61
,
13373
(
2000
).
Google Scholar
 
6.
M.
Helm
,
Semicond. Sci. Technol.
10
,
557
(
1995
).
Google Scholar
 
7.
C.
Waschke
,
H. G.
Roskos
,
R.
Schwedler
,
K.
Leo
,
H.
Kurz
, and
K.
Köhler
,
Phys. Rev. Lett.
70
,
3319
(
1993
).
Google Scholar
 
8.
T.
Dekorsy
,
P.
Leisching
,
K.
Köhler
, and
H.
Kurz
,
Phys. Rev. B
50
,
8106
(
1994
).
Google Scholar
 
9.
K.
Unterrainer
,
B. J.
Keay
,
M. C.
Wanke
,
S. J.
Allen
,
D.
Leonard
,
G.
Medeiros-Ribeiro
,
U.
Bhattacharya
, and
M. J. W.
Rodwell
,
Phys. Rev. Lett.
76
,
2973
(
1996
).
Google Scholar
 
10.
E.
Schomburg
,
T.
Blomeier
,
K.
Hofbeck
,
J.
Grenzer
,
S.
Brandl
,
I.
Lingott
,
A. A.
Ignatov
,
K. F.
Renk
,
D. G.
Pavel’ev
,
Y.
Koschurinov
,
B. Y.
Melzer
,
V. M.
Ustinov
,
S. V.
Ivanov
,
A.
Zhukov
, and
P. S.
Kop’ev
,
Phys. Rev. B
58
,
4035
(
1998
).
Google Scholar
 
11.
R. F.
Kazarinov
and
R. A.
Suris
,
Sov. Phys. Semicond.
6
,
120
(
1972
).
Google Scholar
 
12.
S. A.
Ktitorov
,
G. S.
Simin
, and
V. Y.
Sindalovskii
,
Sov. Phys. Solid State
13
,
1872
(
1971
).
Google Scholar
 
13.
X. L.
Lei
,
N. J. M.
Horing
, and
H. L.
Cui
,
Phys. Rev. Lett.
66
,
3277
(
1991
).
Google Scholar
 
14.
A. A.
Ignatov
,
K. F.
Renk
, and
E. P.
Dodin
,
Phys. Rev. Lett.
70
,
1996
(
1993
).
Google Scholar
 
15.
A.
Wacker
,
G.
Schwarz
,
F.
Prengel
, and
E.
Schöll
,
Phys. Rev. B
52
,
13788
(
1995
).
Google Scholar
 
16.
X.-C.
Zhang
and
D.
Auston
,
J. Appl. Phys.
71
,
326
(
1992
).
Google Scholar
 
17.
H. G.
Roskos
,
M. C.
Nuss
,
J.
Shah
,
K.
Leo
,
D. A. B.
Miller
,
A. M.
Fox
,
S.
Schmitt-Rink
, and
K.
Köhler
,
Phys. Rev. Lett.
68
,
2216
(
1992
).
Google Scholar
 
18.
A.
Leitenstorfer
,
S.
Hunsche
,
J.
Shah
,
M. C.
Nuss
, and
W. H.
Knox
,
Phys. Rev. Lett.
25
,
5140
(
1999
).
Google Scholar
 
19.
R.
Bratschitsch
,
R.
Kersting
,
T.
Müller
,
G.
Strasser
,
K.
Unterrainer
,
W.
Fischler
, and
R. A.
Höpfel
,
Physica B
272
,
375
(
1999
).
Google Scholar
 
20.
R.
Kersting
,
K.
Unterrainer
,
G.
Strasser
,
H. F.
Kauffmann
, and
E.
Gornik
,
Phys. Rev. Lett.
79
,
3038
(
1997
).
Google Scholar
 
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