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

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 نشر من قبل Wei-Feng Tsai
 تاريخ النشر 2009
  مجال البحث فيزياء
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We propose a trilayer $pi$-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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