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arXiv · 0806.0209

Time-reversal symmetry breaking surface states of d-wave superconductors induced by an additional order parameter with negative T_c

Takeshi Tomizawa·Kazuhiro Kuboki
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Abstract

Surface states of d_{x^2-y^2}-wave superconductors are studied using the Ginzburg-Landau (GL) theory. For a [110] surface it has been known that the time-reversal symmetry (T) breaking surface state, (d+-is)-wave state, can occur if the bare transition temperature of the s-wave order parameter (OP) is positive. We show that even if this bare T_c is negative, it is possible to break T because the coupling to the spontaneously generated magnetic field may induce the s-wave OP. The T-breaking state is favored when the GL parameter (kappa) is small.

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Takeshi Tomizawa, Kazuhiro Kuboki. 2008-09-30. Time-reversal symmetry breaking surface states of d-wave superconductors induced by an additional order parameter with negative T_c. https://doi.org/10.1103/physrevb.78.094519

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