An important desired ingredient of superconducting quantum circuits is a readout scheme whose complexity does not increase with the number of qubits involved in the measurement. Here, we present a readout scheme employing a single microwave line, which enables simultaneous readout of multiple qubits. Consequently, scaling up superconducting qubit circuits is no longer limited by the readout apparatus. Parallel readout of 6 flux qubits using a frequency division multiplexing technique is demonstrated, as well as simultaneous manipulation and time resolved measurement of 3 qubits. We discuss how this technique can be scaled up to read out hundreds of qubits on a chip.

1.
L.
DiCarlo
,
M. D.
Reed
,
L.
Sun
,
B. R.
Johnson
,
J. M.
Chow
,
J. M.
Gambetta
,
L.
Frunzio
,
S. M.
Girvin
,
M. H.
Devoret
, and
R. J.
Schoelkopf
,
Nature (London)
467
,
574
(
2010
).
2.
M.
Neeley
,
R. C.
Bialczak
,
M.
Lenander
,
E.
Lucero
,
M.
Mariantoni
,
A. D.
O’Connell
,
D.
Sank
,
H.
Wang
,
M.
Weides
,
J.
Wenner
,
Y.
Yin
,
T.
Yamamoto
,
A. N.
Cleland
, and
J. M.
Martinis
,
Nature (London)
467
,
570
(
2010
).
3.
B. A.
Mazin
,
P. K.
Day
,
K. D.
Irwin
,
C. D.
Reintsema
, and
J.
Zmuidzinas
,
Nucl. Instrum. Methods Phys. Res. A
559
,
799
(
2006
).
4.
S. J. C.
Yates
,
A. M.
Baryshev
,
J. J. A.
Baselmans
,
B.
Klein
, and
R.
Güsten
,
Appl. Phys. Lett.
95
,
042504
(
2009
).
5.
M.
Jerger
,
S.
Poletto
,
P.
Macha
,
U.
Hübner
,
A.
Lukashenko
,
E.
Il’ichev
, and
A. V.
Ustinov
,
Europhys. Lett.
96
,
40012
(
2011
).
6.
T. P.
Orlando
,
J. E.
Mooij
,
L.
Tian
,
C. H.
van der Wal
,
L. S.
Levitov
,
S.
Lloyd
, and
J. J.
Mazo
,
Phys. Rev. B
60
,
15398
(
1999
).
7.
A.
Blais
,
R.-S.
Huang
,
A.
Wallraff
,
S. M.
Girvin
, and
R. J.
Schoelkopf
,
Phys. Rev. A
69
,
062320
(
2004
).
8.
J. R.
Carson
,
Proc. IRE
10
,
57
(
1922
).
You do not currently have access to this content.