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arXiv · cond-mat/9803032

Time-reversal symmetry breaking surface states in t-J model

Kazuhiro Kuboki·Manfred Sigrist
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Abstract

Recently a phenomenological Ginzburg-Landau (GL) theory has been proposed to describe the occurrence of a locally time-reversal symmetry (T) breaking state near a Josephson junction between unconventional superconductors. In this paper we derive this type of GL free energy microscopically from the t-J model within a slave-boson mean-field approximation. The resulting GL free energy is shown to satisfy the conditions to have a T-violating surface state. The existence of this junction state may explain some of the recent experiments on High-Tc superconductors.

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Kazuhiro Kuboki, Manfred Sigrist. 1998-03-03. Time-reversal symmetry breaking surface states in t-J model. https://doi.org/10.1143/jpsj.67.2873

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