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arXiv · 2505.01759

Ferroelectrically Switchable Chirality in Topological Superconductivity

Abstract

The interplay between ferroelectricity, magnetism, and superconductivity provides a rich platform for discovering novel quantum phenomena. Here, we develop an effective theory and propose a heterostructure composed of an antiferromagnetic bilayer MnBi$_{2}$Te$_{4}$ coupled with the s-wave superconductor Fe(Se,Te), enabling the realization of chiral topological superconductivity (CTSC) with switchable chirality. The chirality of the CTSC is controlled by the direction of spontaneous polarization, which arises from interlayer sliding-induced ferroelectricity or charge transfer in the bilayer MnBi$_{2}$Te$_{4}$. This sliding mechanism breaks the $\mathcal{M}_{z}\mathcal{T}$ and $\mathcal{PT}$ symmetries, leading to the anomalous Hall effect in the spin polarized metallic Dirac band and drives the emergence of CTSC when the s-wave superconductivity appears. Our work not only provides a new pathway to achieve and control topological superconductivity but also opens avenues for experimental exploration of Majorana physics and topological quantum computation.

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BibTeXRIS

Kai-Zhi Bai, Bo Fu, Shun-Qing Shen. 2026-01-30. Ferroelectrically Switchable Chirality in Topological Superconductivity. https://arxiv.org/abs/2505.01759

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