arXiv:1405.1969 · Physical Review B

Tunable and switchable coupling between two superconducting resonators

A. Baust, Eric A. Hoffmann, M. Haeberlein, M. J. Schwarz, Peter Eder, Jan Goetz, F. Wulschner, E. Xie, Ling Zhong, Fernando Quijandría, Borja Peropadre, David Zueco, Juan José García‐Ripoll, E. Solano, Kirill G. Fedorov, E. P. Menzel, Frank Deppe, Achim Marx, R. Gross

Published Jan 30, 2015• 68 citations

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Abstract

We realize a device allowing for tunable and switchable coupling between two frequency-degenerate superconducting resonators mediated by an artificial atom. For the latter, we utilize a persistent current flux qubit. We characterize the tunable and switchable coupling in the frequency and time domains and find that the coupling between the relevant modes can be varied in a controlled way. Specifically, the coupling can be tuned by adjusting the flux through the qubit loop or by controlling the qubit population via a microwave drive. Our measurements allow us to find parameter regimes for optimal coupler performance and quantify the tunability range.

DOI: 10.1103/physrevb.91.014515

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