Tilting the balance towards d-wave in iron-based superconductors

Mario Fink; Ronny Thomale

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arXiv · 1704.05525

Tilting the balance towards d-wave in iron-based superconductors

Mario Fink·Ronny Thomale

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Abstract

The intricate interplay of interactions and Fermiology can give rise to a close competition between nodeless (e.g. s-wave) and nodal (e.g. d-wave) order in electronically driven unconventional superconductors. We analyze how such a scenario is affected by a Zeeman magnetic field $H_{\text{Z}}$ and temperature $T$. In the neighborhood of a zero temperature first order critical point separating a nodal from a nodeless phase, the phase boundary at low $H_{\text{Z}}$ and/or low $T$ has a universal line shape cubic in $H_{\text{Z}}$ or $T$, such that the nodal state is stabilized at the expense of the nodeless. We calculate this line shape for a model of competing s_\pm-wave and d-wave pairing in iron-based superconductors.

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Mario Fink, Ronny Thomale. 2017-04-18. Tilting the balance towards d-wave in iron-based superconductors. https://arxiv.org/abs/1704.05525

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