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arXiv · 2605.06852

Fluctuation-driven chiral ferromagnetism

Rokas Veitas·Ahmed Khalifa·Francisco Machado·Shubhayu Chatterjee
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Abstract

Quantum fluctuations are often suppressed in ferromagnetic materials because they admit a simple unfrustrated ground state, greatly limiting the scope of the phenomena that can be observed. In this work, we show how naturally occurring magnetization-non-conserving couplings fundamentally alter this paradigm by demonstrating the existence of a chiral ferromagnet that is stabilized by quantum fluctuations. More specifically, we show how these spin-orbit interactions modify the classical phase diagram; whereas a classical analysis predicts only achiral collinear states, we observe fluctuation-stabilized phases, including a ferromagnet with large orbital chirality and a chiral stripe. We elucidate how such couplings generate a scalar orbital chirality spontaneously, in contrast to conventional mechanisms which rely upon a field-induced canting of vector chiral order. The resultant chiral states exhibit distinct transport signatures, namely an enhanced thermal Hall effect, and are of direct relevance to moir\'e heterostructures, Rydberg-atom arrays, and solid-state materials featuring non-Kramers spins

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Rokas Veitas, Ahmed Khalifa, Francisco Machado, Shubhayu Chatterjee. 2026-05-07. Fluctuation-driven chiral ferromagnetism. https://arxiv.org/abs/2605.06852

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