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Title: Kitaev spin-orbital bilayers and their moiré superlattices

We determine the phase diagram of a bilayer, Yao-Lee spin-orbital model with inter-layer interactions (J), for several stackings and moiré superlattices. For AA stacking, a gapped$${{\mathbb{Z}}}_{2}$$Z2quantum spin liquid phase emerges at a finiteJc. We show that this phase survives in the well-controlled large-Jlimit, where an isotropic honeycomb toric code emerges. For moiré superlattices, a finite-qinter-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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Nature Publishing Group
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Journal Name:
npj Quantum Materials
Medium: X
Sponsoring Org:
National Science Foundation
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