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arXiv · 2310.12002

Topological states of multiband superconductors with interband pairing

M. F. Holst·M. Sigrist·K. V. Samokhin
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Abstract

We study the effects of interband pairing in two-band s-wave and d-wave superconductors with D4h symmetry in both time-reversal invariant as well as time-reversal symmetry breaking states. The presence of interband pairing qualitatively changes the nodal structure of the superconductor: nodes can (dis)appear, merge, and leave high-symmetry locations when interband pairing is tuned. Furthermore, in the d-wave case, we find that also the boundary modes change qualitatively when interband pairing increases: flat zero-energy Andreev bound states gap out and transition to helical edge states.

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M. F. Holst, M. Sigrist, K. V. Samokhin. 2023-10-18. Topological states of multiband superconductors with interband pairing. https://arxiv.org/abs/2310.12002

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