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arXiv · 1301.5164

Josephson vortex coupled to a flux qubit

Kirill G. Fedorov·Anastasia V. Shcherbakova·Roland Schäfer·Alexey V. Ustinov
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Abstract

Experiments towards realizing a readout of superconducting qubits by using ballistic Josephson vortices are reported. We measured the microwave radiation induced by a fluxon moving in an annular Josephson junction. By coupling a flux qubit as a current dipole to the annular junction, we detect periodic variations of the fluxon's oscillation frequency versus magnetic flux through the qubit. We found that the scattering of a fluxon on a current dipole can lead to the acceleration of a fluxon regardless of a dipole polarity. We use the perturbation theory and numerical simulations of the perturbed sine-Gordon equation to analyze our results.

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Kirill G. Fedorov, Anastasia V. Shcherbakova, Roland Schäfer, Alexey V. Ustinov. 2013-01-22. Josephson vortex coupled to a flux qubit. https://doi.org/10.1063/1.4800585

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