title: Suppression of Dephasing by Qubit Motion in Superconducting Circuits.
abstract: We suggest and demonstrate a protocol which suppresses the low-frequency dephasing by qubit motion, i.e., transfer of the logical qubit of information in a system of n≥2 physical qubits. The protocol requires only the nearest-neighbor coupling and is applicable to different qubit structures. Our analysis of its effectiveness against noises with arbitrary correlations, together with experiments using up to three superconducting qubits, shows that for the realistic uncorrelated noises, qubit motion increases the dephasing time of the logical qubit as √n. In general, the protocol provides a diagnostic tool for measurements of the noise correlations.
authors.affiliation: Department of Physics and Astronomy, Stony Brook University, SUNY, Stony Brook, New York 11794-3800, USA.
authors.forename: D V
authors.initials: DV
authors.lastname: Averin
authors.affiliation: Department of Physics, Zhejiang University, Hangzhou, Zhejiang 310027, China.
authors.forename: K
authors.initials: K
authors.lastname: Xu
authors.affiliation: Department of Physics, Zhejiang University, Hangzhou, Zhejiang 310027, China.
authors.forename: Y P
authors.initials: YP
authors.lastname: Zhong
authors.affiliation: Department of Physics, Zhejiang University, Hangzhou, Zhejiang 310027, China.
authors.forename: C
authors.initials: C
authors.lastname: Song
authors.affiliation: Department of Physics, Zhejiang University, Hangzhou, Zhejiang 310027, China.
authors.forename: H
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Physics and Astronomy, University of Kansas, Lawrence, Kansas 66045, USA.
authors.forename: Siyuan
authors.initials: S
authors.lastname: Han