Odd-parity magnetism by quantum geometry

Kanta Kudo; Youichi Yanase

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arXiv · 2505.20907

Odd-parity magnetism by quantum geometry

Kanta Kudo·Youichi Yanase

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Abstract

We uncover a geometric mechanism of odd-parity multipole magnetism driven by the quantum metric of Bloch electrons. By analyzing spin and odd-parity multipole susceptibilities in a multi-sublattice model, we demonstrate that the quantum metric directly controls the instability toward odd-parity magnetic multipole order over a wide range of parameters, which condenses under Hubbard interaction. The resulting state exhibits complex magnetic correlations, as a hallmark of quantum-geometric magnetism. These results establish a geometric design principle for odd-parity multipole magnets and provide a route toward the experimental verification of quantum-geometric magnetism.

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Kanta Kudo, Youichi Yanase. 2025-05-27. Odd-parity magnetism by quantum geometry. https://arxiv.org/abs/2505.20907

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