Theory of a quantum spin liquid in hydrogen-intercalated honeycomb iridate, H3LiIr2O6

Abstract

We propose a theoretical model for a gapless spin liquid phase that may have been observed in a recent experiment on ${\mathrm{H}}_3\mathrm{LiI}{\mathrm{r}}_2{\mathrm{O}}_6$. Despite the insulating and non-magnetic nature of the material, the specific heat coefficient $C/T\sim 1/\sqrt{T}$ in zero magnetic field and $C/T\sim T/B^{3/2}$ with finite magnetic field $B$ have been observed. In addition, the NMR relaxation rate shows $1/(T_{1}T)\sim (C/T{)}^2$. Motivated by the fact that the interlayer/in-plane lattice parameters are reduced/elongated by the hydrogen-intercalation of the parent compound $\mathrm{L}{\mathrm{i}}_2\mathrm{Ir}{\mathrm{O}}_3$, we consider four layers of the Kitaev honeycomb lattice model with additional interlayer exchange interactions. It is shown that the resulting spin liquid excitations reside mostly in the top and bottom layers of such a layered structure and possess a quartic dispersion. In an applied magnetic field, each quartic mode is split into four Majorana cones with the velocity $v\sim B^{3/4}$. We suggest that the spin liquid phase in these "defect" layers, placed between different stacking patterns of the honeycomb layers, can explain the major phenomenology of the experiment, which can be taken as evidence that the Kitaev interaction plays the primary role in the formation of a quantum spin liquid in this material.

5+2 pages, 4+1 figures; published version

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Cited by in corpus (23)

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• Competition between static and dynamic magnetism in the Kitaev spin liquid material Cu2IrO3
• Role of Hydrogen in the spin-orbital-entangled quantum liquid candidate H${}_3$LiIr${}_2$O${}_6$
• Magnetic field-induced evolution of intertwined orders in the Kitaev magnet $\beta$-Li${}_2$IrO${}_3$
• Tunneling spectroscopy as a probe of fractionalization in 2D magnetic heterostructures
• Quantum Paraelectricity in the Kitaev Quantum-Spin-Liquid Candidates H${}_3$LiIr${}_2$O${}_6$ and D${}_3$LiIr${}_2$O${}_6$
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• Dynamical structure factor in the non-Abelian phase of the Kitaev honeycomb model in the presence of quenched disorder
• Possible Quantum Paraelectric State in Kitaev Spin Liquid Candidate H${}_3$LiIr${}_2$O${}_6$
• Dynamics of fractionalized mean-field theories: consequences for Kitaev materials
• Raman Scattering Polarization and Single Spinon Identification in Two-Dimensional Kitaev Quantum Spin Liquids
• Engineering the Kitaev spin liquid in a quantum dot system
• Projective-symmetry-group analysis of inelastic light scattering in Kitaev spin balls
• Gauge Field Dynamics in Multilayer Kitaev Spin Liquids
• Even-odd effect in multilayer Kitaev honeycomb magnets