Approaching unit visibility for control of a superconducting qubit with dispersive readout.
In a Rabi oscillation experiment with a superconducting qubit we show that a visibility in the qubit excited state population of more than 95% can be attained. We perform a dispersive measurement of the qubit state by coupling the qubit non-resonantly to a transmission line resonator and probing the resonator transmission spectrum. The measurement process is well characterized and quantitatively understood. In a measurement of Ramsey fringes, the qubit coherence time is larger than 500 ns.
Wallraff
A
A
Department of Applied Physics, Yale University, New Haven, Connecticut 06520, USA.
Schuster
D I
DI
Blais
A
A
Frunzio
L
L
Majer
J
J
Devoret
M H
MH
Girvin
S M
SM
Schoelkopf
R J
RJ