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arXiv · 2312.03879

Field-driven transition from quantum spin liquid to magnetic order in triangular-lattice antiferromagnets

Santanu Dey·Joseph Maciejko·Matthias Vojta
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Abstract

Recently several triangular-lattice magnets with delafossite structure have been found to display spin-liquid behavior down to the lowest temperatures. Remarkably, applying a magnetic field destroys the spin liquid which then gives way to symmetry-breaking states, identified as semiclassical coplanar states including a magnetization plateau at 1/3 total magnetization. Here we provide a theoretical approach rationalizing this dichotomy, utilizing a Schwinger-boson theory that captures both ordered and disordered magnetic phases. We show that a zero-field spin liquid, driven by strong frustration, is naturally destabilized in a magnetic field via spinon condensation. Symmetry-breaking order akin to the standard triangular-lattice Heisenberg model then arises via an order-by-disorder mechanism. We discuss implications for pertinent experiments.

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Santanu Dey, Joseph Maciejko, Matthias Vojta. 2023-12-06. Field-driven transition from quantum spin liquid to magnetic order in triangular-lattice antiferromagnets. https://doi.org/10.1103/physrevb.109.224424

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