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arXiv · 2203.03650

Kitaev spin-orbital bilayers and their moir\'e superlattices

Emilian Nica·Muhammad Akram·Aayush Vijayvargia·Roderich Moessner·Onur Erten
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Abstract

We determine the phase diagram of a bilayer, Yao-Lee spin-orbital model with inter-layer interactions (J), for several stackings and moir\'e superlattices. For AA stacking, a gapped Z2 quantum spin liquid phase emerges at a finite Jc. We show that this phase survives in the well-controlled large-J limit, where an isotropic honeycomb toric code emerges. For moir\'e superlattices, a finite-q inter-layer hybridization is stabilized. This connects inequivalent Dirac points, effectively `untwisting' the system. Our study thus provides insight into the spin-liquid phases of bilayer spin-orbital Kitaev materials.

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Emilian Nica, Muhammad Akram, Aayush Vijayvargia, Roderich Moessner, Onur Erten. 2022-03-07. Kitaev spin-orbital bilayers and their moir\'e superlattices. https://doi.org/10.1038/s41535-023-00541-2

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