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arXiv · 0904.3784

A Compound Josephson Junction Coupler for Flux Qubits With Minimal Crosstalk

R. Harris·T. Lanting·A. J. Berkley·J. Johansson·M. W. Johnson·P. Bunyk·E. Ladizinsky·N. Ladizinsky·T. Oh·Siyuan Han
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Abstract

An improved tunable coupling element for building networks of coupled rf-SQUID flux qubits has been experimentally demonstrated. This new form of coupler, based upon the compound Josephson junction rf-SQUID, provides a sign and magnitude tunable mutual inductance between qubits with minimal nonlinear crosstalk from the coupler tuning parameter into the qubits. Quantitative agreement is shown between an effective one-dimensional model of the coupler's potential and measurements of the coupler persistent current and susceptibility.

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R. Harris, T. Lanting, A. J. Berkley, J. Johansson, M. W. Johnson, P. Bunyk, E. Ladizinsky, N. Ladizinsky, T. Oh, Siyuan Han. 2009-04-24. A Compound Josephson Junction Coupler for Flux Qubits With Minimal Crosstalk. https://doi.org/10.1103/physrevb.80.052506

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