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Frustrated two-dimensional Josephson junction array near incommensurability

In-Cheol Baek·Young-Je Yun·Mu-Yong Choi
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Abstract

To study the properties of frustrated two-dimensional Josephson junction arrays near incommensurability, we examine the current-voltage characteristics of a square proximity-coupled Josephson junction array at a sequence of frustrations f=3/8, 8/21, 0.382 $(\approx (3-\sqrt{5})/2)$, 2/5, and 5/12. Detailed scaling analyses of the current-voltage characteristics reveal approximately universal scaling behaviors for f=3/8, 8/21, 0.382, and 2/5. The approximately universal scaling behaviors and high superconducting transition temperatures indicate that both the nature of the superconducting transition and the vortex configuration near the transition at the high-order rational frustrations f=3/8, 8/21, and 0.382 are similar to those at the nearby simple frustration f=2/5. This finding suggests that the behaviors of Josephson junction arrays in the wide range of frustrations might be understood from those of a few simple rational frustrations.

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In-Cheol Baek, Young-Je Yun, Mu-Yong Choi. 2004-05-06. Frustrated two-dimensional Josephson junction array near incommensurability. https://doi.org/10.1103/physrevb.69.172501

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