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arXiv · 2602.14507

Reentrant Superconductivity in Zeeman Fields

Tomoya Sano·Kota Tabata·Satoshi Ikegaya·Yasuhiro Asano
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Abstract

We propose a theoretical model for a superconductor that exhibits the reentrant superconductivity in Zeeman fields. The Bogoliubov-de Gennes Hamiltonian includes three vectors in spin space: a $d$ vector of a spin-triplet superconducting state, a potential representing spin-orbit interactions, and a Zeeman field. When the three vectors are perpendicular to one another, the spin-orbit interaction suppresses superconductivity in weak Zeeman fields and enhances superconductivity in strong Zeeman fields. The instability (stability) of superconducting state is characterized by the appearance of odd-frequency (even-frequency) Cooper pairs.

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Tomoya Sano, Kota Tabata, Satoshi Ikegaya, Yasuhiro Asano. 2026-02-16. Reentrant Superconductivity in Zeeman Fields. https://arxiv.org/abs/2602.14507

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