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arXiv · 2503.06642

Magnon-mediated superconductivity on ferromagnetic wallpaper fermions

Koki Mizuno·Ai Yamakage
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Abstract

We study two-dimensional superconductivity mediated by magnetic fluctuations at the interface between a ferromagnetic insulator and the nonsymmorphic topological crystalline insulator with a fourfold-degenerate Dirac point, wallpaper fermion. We demonstrate that BCS pairing with zero center-of-mass momentum induces chiral $p$-wave superconductivity, and the Amperean pairing with center-of-mass momentum $2k_{\rm F}$ can give rise to a parity-mixed superconducting state. We find that the Amperean pairing exhibits a mixture of $s$-wave and $p$-wave components due to the multiband nature of the wallpaper fermion and the easy-axis anisotropy of the ferromagnetic insulator. Additionally, we find that the stability of the superconducting state with BCS and the Amperean pairing is governed by the easy-axis anisotropy.

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Koki Mizuno, Ai Yamakage. 2025-03-09. Magnon-mediated superconductivity on ferromagnetic wallpaper fermions. https://doi.org/10.1103/sknv-r7wq

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