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arXiv · cond-mat/0510033

Frustration phenomena in Josephson junction arrays on a dice lattice

M. Tesei·R. Theron·P. Martinoli
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Abstract

AC magnetoimpedance measurements performed on proximity-effect coupled Josephson junction arrays on a dice lattice reveal unconventional behaviour resulting from the interplay between the frustration f created by the applied magnetic field and the particular geometry of the system. While the inverse magnetoinductance exhibits prominent peaks at f=1/3 and at f=1/6 (and weaker structures at f=1/9,2/9,1/12,...) reflecting vortex states with a high degree of superconducting phase coherence, the deep minimum at f=1/2 points to a state in which the phase coherence is strongly suppressed. These observations are discussed at the light of recent theoretical work in which the concept of accidental degeneracy plays a central role.

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M. Tesei, R. Theron, P. Martinoli. 2005-10-03. Frustration phenomena in Josephson junction arrays on a dice lattice. https://doi.org/10.1016/j.physc.2005.12.090

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