Double quantum dots were formed in a gated GaAs/AlGaAs heterostructure with negligible interdot tunneling; strong capacitive coupling was provided by a floating interdot capacitor. The interdot capacitance was measured to be 0.28CΣ, where CΣ is the single-dot capacitance. Coulomb blockade conductance images for both dots versus side gate voltages at 70 mK show a hexagonal pattern of peaks; the double dot acts as a single-electron current switch. For weak tunneling, the conductance peaks of both dots fit thermally broadened line shapes. Charge fluctuations produced by strong tunneling on one dot are induced on the second, filling in its peak splitting.

1.
H.
Grabert
and
M. H.
Devoret
, NATO ASI Ser., Ser. B 294, (1992), and references contained therein.
2.
L. L.
Sohn
,
L. P.
Kouwenhoven
, and
G.
Schön
, NATO ASI Ser., Ser. E 345, (1997), and references contained therein.
3.
K. K.
Likharev
,
Proc. IEEE
87
,
606
(
1999
), and references contained therein.
4.
C.
Livermore
,
C. H.
Crouch
,
R. M.
Westervelt
,
K. L.
Campman
, and
A. C.
Gossard
,
Science
274
,
1332
(
1996
).
5.
N. C.
van der Vaart
,
S. F.
Godijn
,
Y. V.
Nazarov
,
C. J. P. M.
Harmans
,
J. E.
Mooij
,
L. W.
Molenkamp
, and
C. T.
Foxon
,
Phys. Rev. Lett.
74
,
4702
(
1995
).
6.
F. R.
Waugh
,
M. J.
Berry
,
D. J.
Mar
,
R. M.
Westervelt
,
K. L.
Campman
, and
A. C.
Gossard
,
Phys. Rev. Lett.
75
,
705
(
1995
).
7.
F.
Hofmann
,
T.
Heinzel
,
D. A.
Wharam
,
J. P.
Kotthaus
,
G.
Böhm
,
W.
Klein
,
G.
Tränkle
, and
G.
Weimann
,
Phys. Rev. B
51
,
13
872
(
1995
).
8.
R. H.
Blick
,
R. J.
Haug
,
J.
Weiss
,
D.
Pfannkuche
,
K. v.
Klitzing
, and
K.
Eberl
,
Phys. Rev. B
53
,
7899
(
1996
).
9.
D.
Dixon
,
L. P.
Kouwenhoven
,
P. L.
McEuen
,
Y.
Nagamune
,
J.
Motohisa
, and
N.
Sakaki
,
Phys. Rev. B
53
,
12
625
(
1996
).
10.
D.
Loss
and
D. P.
DiVincenzo
,
Phys. Rev. A
57
,
120
(
1998
).
11.
D. S.
Duncan
,
C.
Livermore
,
R. M.
Westervelt
,
K. D.
Maranowski
, and
A. C.
Gossard
,
Appl. Phys. Lett.
74
,
1045
(
1999
)
12.
C.
Livermore
,
D. S.
Duncan
,
R. M.
Westervelt
,
K. D.
Maranowski
, and
A. C.
Gossard
,
J. Appl. Phys.
86
,
4043
(
1999
).
This content is only available via PDF.
You do not currently have access to this content.