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Switchable resonant coupling of flux qubits

M. Grajcar·Yu-xi Liu·Franco Nori·A. M. Zagoskin
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Abstract

We propose a coupling scheme, where two or more flux qubits with different eigenfrequencies share Josephson junctions with a coupler loop devoid of its own quantum dynamics. Switchable two-qubit coupling is realized by tuning the frequency of the AC magnetic flux through the coupler to a combination frequency of two of the qubits. The coupling allows any or all of the qubits to be simultaneously at the degeneracy point and can change sign.

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M. Grajcar, Yu-xi Liu, Franco Nori, A. M. Zagoskin. 2006-11-30. Switchable resonant coupling of flux qubits. https://doi.org/10.1103/physrevb.74.172505

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