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arXiv · 1503.04653

Dc SQUID based on a three-band superconductor with broken time-reversal symmetry

Y. S. Yerin·A. N. Omelyanchouk·E. Il'ichev
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Abstract

The behavior of a dc SQUID, based on a dirty point contacts between a single-band and three-band superconductor with broken time-reversal symmetry is investigated. Using earlier obtained results for Josephson effects in such systems new features in characteristics of a dc SQUID are revealed. It is shown that in the case of a BTRS (broken time-reversal symmetry) three-band superconductor for the applied external magnetic flux, which is divisible by the half-integer flux, strong degeneracy of ground states of a dc SQUID is taken place. This can lead to the appearance of possible multi-hysteresis loops on a dependence of a total flux in the dc SQUID from the externally applied flux. The number of these loops depends on the position of ground states of a three-band superconductor. Also it is found that dependencies of a critical current on applied magnetic flux can have complicated multi-periodic forms, which are differ from strictly periodic characteristics for conventional dc SQUIDs and Fraunhofer patterns for Josephson contacts in the external magnetic field.

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Y. S. Yerin, A. N. Omelyanchouk, E. Il'ichev. 2015-03-16. Dc SQUID based on a three-band superconductor with broken time-reversal symmetry. https://doi.org/10.1088/0953-2048%2F28%2F9%2F095006

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