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Aharonov-Casher-Effect Suppression of Macroscopic Tunneling of Magnetic Flux

Jonathan R. Friedman·D. V. Averin
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Abstract

We suggest a system in which the amplitude of macroscopic flux tunneling can be modulated via the Aharonov-Casher effect. The system is an rf-SQUID with the Josephson junction replaced by a Bloch transistor -- two junctions separated by a small superconducting island on which the charge can be induced by an external gate voltage. When the Josephson coupling energies of the junctions are equal and the induced charge is q=e, destructive interference between tunneling paths brings the flux tunneling rate to zero. The device may also be useful as a qubit for quantum computation.

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Jonathan R. Friedman, D. V. Averin. 2001-09-28. Aharonov-Casher-Effect Suppression of Macroscopic Tunneling of Magnetic Flux. https://doi.org/10.1103/physrevlett.88.050403

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