Quantum coherent tunable coupling of superconducting qubits.
To do large-scale quantum information processing, it is necessary to control the interactions between individual qubits while retaining quantum coherence. To this end, superconducting circuits allow for a high degree of flexibility. We report on the time-domain tunable coupling of optimally biased superconducting flux qubits. By modulating the nonlinear inductance of an additional coupling element, we parametrically induced a two-qubit transition that was otherwise forbidden. We observed an on/off coupling ratio of 19 and were able to demonstrate a simple quantum protocol.
Niskanen
A O
AO
CREST, Japan Science and Technology Institute, Kawaguchi, Saitama 332-0012, Japan.
Harrabi
K
K
Yoshihara
F
F
Nakamura
Y
Y
Lloyd
S
S
Tsai
J S
JS