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arXiv · 0812.0661

Novel properties in Josephson junctions involving the cos(kx)cos(ky)-pairing state in iron-pnictides

Wei-Feng Tsai·Dao-Xin Yao·B. Andrei Bernevig·JiangPing Hu
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Abstract

We propose a trilayer $π$-junction that takes advantage of the unconventional $s_{x^2 y^2}=\cos k_x \cos k_y$ pairing symmetry which changes sign between electron and hole Fermi pockets in the iron pnictides. In addition, we also present theoretical results for Andreev bound states in thin superconductor-normal metal (or insulator) iron-pnictide junctions. The presence of nontrivial in-gap states, which uniquely appear in this unconventional pairing state, is a distinct feature in comparison to other singlet pairing states.

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Wei-Feng Tsai, Dao-Xin Yao, B. Andrei Bernevig, JiangPing Hu. 2009-08-04. Novel properties in Josephson junctions involving the cos(kx)cos(ky)-pairing state in iron-pnictides. https://doi.org/10.1103/physrevb.80.012511

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