Kitaev spin-orbital bilayers and their moiré superlattices

Abstract

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 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 moiré 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.

23 pages, 6 figures; To appear in npj Quantum Materials

References in corpus (7)

• Possible Kitaev Quantum Spin Liquid State in 2D Materials with S=3/2
• Microscopic mechanism for higher-spin Kitaev model
• A $\Gamma$-matrix generalization of the Kitaev model
• Magnetization textures in twisted bilayer 2D CrX${}_3$ (X=Br, I)
• A Z${}_2$ spin-orbital liquid state in the square lattice Kugel-Khomskii model
• Order Fractionalization in a Kitaev-Kondo model
• Low temperature properties in the Bilayer Kitaev model

Cited by in corpus (11)

• A Kitaev-type spin liquid on a quasicrystal
• Vison crystals, chiral and crystalline phases in the Yao-Lee model
• Electromagnetic signatures of chiral quantum spin liquid
• Magnetic fragmentation and fractionalized Goldstone modes in a bilayer quantum spin liquid
• Microscopic Roadmap to a Yao-Lee Spin-Orbital Liquid
• Topological and magnetic phase transitions in the bilayer Kitaev-Ising model
• Magnetic order through Kondo coupling to quantum spin liquids
• Fractionalized fermionic multicriticality in anisotropic Kitaev spin-orbital liquids
• Emergence of Meron Kekulé lattices in twisted Néel antiferromagnets
• Thermal and quantum fluctuations in extended Kitaev-Yao-Lee spin-orbital model
• Exactly solvable spin liquids in Kitaev bilayers and moiré superlattices