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Instabilities at [110] Surfaces of d_{x^2-y^2} Superconductors

Carsten Honerkamp·Katsunori Wakabayashi·Manfred Sigrist
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Abstract

We compare different scenarios for the low temperature splitting of the zero-energy peak in the local density of states at (110) surfaces of d_{x^2-y^2}-wave superconductors, observed by Covington et al. (Phys.Rev.Lett.79 (1997), 277). Using a tight binding model in the Bogolyubov-de Gennes treatment we find a surface phase transition towards a time-reversal symmetry breaking surface state carrying spontaneous currents and an s+id-wave state. Alternatively, we show that electron correlation leads to a surface phase transition towards a magnetic state corresponding to a local spin density wave state.

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Carsten Honerkamp, Katsunori Wakabayashi, Manfred Sigrist. 1999-02-02. Instabilities at [110] Surfaces of d_{x^2-y^2} Superconductors. https://doi.org/10.1209/epl%2Fi2000-00280-2

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