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arXiv · 0802.2351

Discontinuous current-phase relations in small 1D Josephson junction arrays

Jens Koch·Karyn Le Hur
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Abstract

We study the Josephson effect in small one-dimensional (1D) Josephson junction arrays. For weak Josephson tunneling, topologically different regions in the charge-stability diagram generate distinct current-phase relationships (I$Φ$). We present results for a three-junction system in the vicinity of charge degeneracy lines and triple points. We explain the generalization to larger arrays, show that discontinuities of the I$Φ$ at phase $π$ persist and that, at maximum degeneracy, the problem can be mapped to a tight-binding model providing analytical results for arbitrary system size.

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Jens Koch, Karyn Le Hur. 2008-02-16. Discontinuous current-phase relations in small 1D Josephson junction arrays. https://doi.org/10.1103/physrevlett.101.097007

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