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arXiv · 0801.3761

Magnetic flux noise in the three Josephson junctions superconducting ring

E. Il'ichev·A. N. Omelyanchouk
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Abstract

We analyze the influence of noise on magnetic properties of a su- perconducting loop which contains three Josephson junctions. This circuit is a classical analog of a persistent current (flux) qubit. A loop supercurrent induced by external magnetic field in the presence of thermal fluctuations is calculated. In order to get connection with experiment we calculate the impedance of the low-frequency tank cir- cuit which is inductively coupled with a loop of interest. We compare obtained results with the results in quantum mode - when the three junction loop exhibits quantum tunneling of the magnetic flux. We demonstrate that the tank-loop impedance in the classical and quan- tum modes have different temperature dependence and can be easily distinguished experimentally.

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E. Il'ichev, A. N. Omelyanchouk. 2008-01-24. Magnetic flux noise in the three Josephson junctions superconducting ring. https://doi.org/10.1063/1.2920076

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