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arXiv · 2607.01815

Evidence for Deconfined Magnetic Order in the Kitaev-$J_3$ Model

Jiucai Wang·Chuan Chen
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Abstract

We investigate the Kitaev-$J_3$ honeycomb model using variational Monte Carlo calculations combined with a vison-quasiparticle analysis of the parent Kitaev spin liquid (KSL). We provide evidence for deconfined magnetic phases in which zigzag or antiferromagnetic order coexists with remnant $\mathbb{Z}_2$ topological structure inherited from the KSL. The optimized variational wave functions retain multiple linearly independent topological sectors on a torus, whereas those of conventional ordered phases collapse to a single sector. The vison-quasiparticle analysis shows that magnetic order naturally arises from vison-pair condensation while single visons remain gapped, yielding a microscopic mechanism for magnetic ordering without immediate confinement. The resulting phases further host gapless spinons with multiple Majorana cones, offering a possible microscopic scenario for the anomalous low-temperature longitudinal thermal transport reported in magnetically ordered Kitaev materials such as Na$_2$Co$_2$TeO$_6$. Our results reveal a microscopic route to fractionalized magnetism beyond the conventional dichotomy between magnetic order and spin-liquid behavior.

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Jiucai Wang, Chuan Chen. 2026-07-02. Evidence for Deconfined Magnetic Order in the Kitaev-$J_3$ Model. https://arxiv.org/abs/2607.01815

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