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.
@article{arxiv.2203.03650,
title = {Kitaev spin-orbital bilayers and their moir\'e superlattices},
author = {Emilian Nica and Muhammad Akram and Aayush Vijayvargia and Roderich Moessner and Onur Erten},
journal= {arXiv preprint arXiv:2203.03650},
year = {2023}
}
Comments
23 pages, 6 figures; To appear in npj Quantum Materials