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Generalized switchable coupling for superconducting qubits using double resonance

S. Ashhab·Shigemasa Matsuo·Noriyuki Hatakenaka·Franco Nori
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Abstract

We propose a method for switchable coupling between superconducting qubits using double resonance. The inter-qubit coupling is achieved by applying near-resonant oscillating fields to the two qubits. The deviation from resonance relaxes the criterion of strong driving fields while still allowing for a fully entangling two-qubit gate. This method avoids some of the shortcomings of previous proposals for switchable coupling. We discuss the possible application of our proposal to a pair of inductively coupled flux qubits, and we consider the extension to phase qubits.

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S. Ashhab, Shigemasa Matsuo, Noriyuki Hatakenaka, Franco Nori. 2006-11-07. Generalized switchable coupling for superconducting qubits using double resonance. https://doi.org/10.1103/physrevb.74.184504

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