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arXiv · 2609.30791

Topological Superconducting Phases in a Strained Altermagnet-Superconductor Heterostructure

Keita Yoshizawa·Ryo Okugawa·Takami Tohyama
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Abstract

We investigate topological superconductivity in a heterostructure consisting of a two-dimensional $s$-wave superconductor and a $d$-wave altermagnet with Rashba spin-orbit coupling. In particular, we study the effects of strain and hopping anisotropy on the topological superconducting phases. By calculating the Chern number, we obtain topological phase diagrams as functions of the chemical potential and the strength of the effective magnetic field induced by the magnetic proximity effect. We find that strain-induced lattice distortion allows topological superconducting phases to emerge over a broad parameter region. Our findings suggest that strain that lowers symmetry can serve as a route to realizing topological superconductivity in altermagnet-superconductor heterostructures.

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Keita Yoshizawa, Ryo Okugawa, Takami Tohyama. 2026-09-25. Topological Superconducting Phases in a Strained Altermagnet-Superconductor Heterostructure. https://arxiv.org/abs/2609.30791

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