Instabilities of spin-1 Kitaev spin liquid phase in presence of single-ion anisotropies

Abstract

We study the spin-one Kitaev model on the honeycomb lattice in the presence of single-ion anisotropies. We consider two types of single ion anisotropies: A $D_{111}$ anisotropy which preserves the symmetry between $X$, $Y$, and $Z$ bonds but violates flux conservation and a $D_{100}$ anisotropy that breaks the symmetry between $X$, $Y$, and $Z$ bonds but preserves flux conservation. We use series expansion methods, degenerate perturbation theory, and exact diagonalization to study these systems. Large positive $D_{111}$ anisotropy leads to a simple product ground state with conventional magnon-like excitations, while large negative $D_{111}$ leads to a broken symmetry and degenerate ground states. For both signs there is a phase transition at a small $|D_{111}|\approx 0.12$ separating the more conventional phases from the Kitaev spin liquid phase. With large $D_{100}$ anisotropy, the ground state is a simple product state, but the model lacks conventional dispersive excitations due to the large number of conservation laws. Large negative $D_{100}$ leads to decoupled one-dimensional systems and many degenerate ground states. No evidence of a phase transition is seen in our numerical studies at any finite $D_{100}$. Convergence of the series expansion extrapolations all the way to $D_{100}=0$ suggests that the nontrivial Kitaev spin liquid is a singular limit of this type of single-ion anisotropy going to zero, which also restores symmetry between the $X$, $Y$, and $Z$ bonds.

7 pages and 8 figures. v2: Matches published version

References in corpus (16)

• Mott Insulators in the Strong Spin-Orbit Coupling Limit: From Heisenberg to a Quantum Compass and Kitaev Models
• Exact results for spin dynamics and fractionization in the Kitaev Model
• Topological characterization of quantum phase transitions in a S=1/2 spin model
• Exact results on the Kitaev model on a hexagonal lattice: spin states, string and brane correlators, and anyonic excitations
• Autocorrelations and Thermal Fragility of Anyonic Loops in Topologically Quantum Ordered Systems
• Raman Scattering Signatures of Kitaev Spin Liquids in A${}_2$ IrO${}_3$ Iridates
• Microscopic mechanism for higher-spin Kitaev model
• Spin-S Kitaev model: Classical Ground States, Order by Disorder and Exact Correlation Functions
• Emergent Fermions and Anyons in the Kitaev Model
• Thermodynamic Evidence of Proximity to a Kitaev Spin-Liquid in Ag${}_3$LiIr${}_2$O${}_6$
• Vacancy-induced low-energy density of states in the Kitaev spin liquid
• Unusual excitations and double-peak specific heat in a bond-alternating spin-$1$ $K$-$\Gamma$ chain
• Excitation spectrum of spin-1 Kitaev spin liquids
• Instabilities of spin-1 Kitaev spin liquid phase in presence of single-ion anisotropies
• Anisotropy as a diagnostic test for distinct tensor network wavefunctions of integer and half-integer spin Kitaev quantum spin liquids
• Quantum phase transitions in the spin-1 Kitaev-Heisenberg chain

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• Signatures of Kitaev interactions in the van der Waals ferromagnet VI3
• Spin-$S$ Kitaev-Heisenberg model on the honeycomb lattice: A high-order treatment via the many-body coupled cluster method
• Symmetries and anomalies of Kitaev spin-$S$ models: Identifying symmetry-enforced exotic quantum matter
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