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arXiv · 0901.1895

0-$π$ phase shifts in Josephson junctions as a signature for the $s_{\pm}$-wave pairing state

Jacob Linder·Iver B. Sperstad·Asle Sudbø
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Abstract

We investigate Josephson junctions with superconducting ferropnictides, both in the diffusive and ballistic limit. We focus on the proposed $s_\pm$-wave state, and find that the relative phase shift intrinsic to the $s_\pm$-wave state may provide 0-$π$ oscillations in the Josephson current. This feature can be used to discriminate this pairing state from the conventional s-wave symmetry. The 0-$π$ oscillations appear both as a function of the ratio of the interface resistances for each band and, more importantly, as a function of temperature, which greatly aids in their detection.

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Jacob Linder, Iver B. Sperstad, Asle Sudbø. 2009-06-18. 0-$π$ phase shifts in Josephson junctions as a signature for the $s_{\pm}$-wave pairing state. https://arxiv.org/abs/0901.1895

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