Proximity superconductivity in chiral kagome antiferromagnets

Adam Yanis Chaou; Gal Lemut; Felix von Oppen; Piet W. Brouwer

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arXiv · 2508.08372

Proximity superconductivity in chiral kagome antiferromagnets

Adam Yanis Chaou·Gal Lemut·Felix von Oppen·Piet W. Brouwer

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Abstract

Recent experiments on the chiral kagome antiferromagnet Mn$_3$Ge have provided strong evidence of proximity-induced spin-polarized superconductivity. We introduce and explore a minimal model which exhibits a rich phase diagram as a function of chemical potential and spin canting. We find a valley-singlet superconducting phase for chemical potentials and canting consistent with the experimental system. This phase transitions into a Chern insulator at larger canting and gives way to topological superconducting phases with Chern numbers ${\cal C}_{\rm BdG} = \pm 1, \pm 3$ at other chemical potentials. Our results show that proximity-induced superconductivity in kagome antiferromagnets is a promising route towards exotic superconductivity with spin-polarized Cooper pairs, with potential applications in spintronics.

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Adam Yanis Chaou, Gal Lemut, Felix von Oppen, Piet W. Brouwer. 2025-08-11. Proximity superconductivity in chiral kagome antiferromagnets. https://arxiv.org/abs/2508.08372

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