Testing Ising Topological Order in $\alpha$-RuCl${}_3$ Under In-Plane Magnetic Fields

Abstract

Material realization of the non-Abelian Kitaev spin liquid phase - an example of Ising topological order (ITO) - has been the subject of intense research in recent years. The $4d$ honeycomb Mott insulator $\alpha$-RuCl${}_3$ has emerged as a leading candidate, as it enters a field-induced magnetically disordered state where a half-integer quantized thermal Hall conductivity ${\kappa }_{xy}$ was reported. Further, a recent report of a sign change in the quantized ${\kappa }_{xy}$ across a certain crystallographic direction is strong evidence for a topological phase transition between two ITOs with opposite Chern numbers. Although this is a fascinating result, independent verification remains elusive, and one may ask if there is a thermodynamic quantity sensitive to the phase transition. Here we propose that the magnetotropic coefficient $k$ under in-plane magnetic fields would serve such a purpose. We report a singular feature in $k$ that indicates a topological phase transition across the $\hat{b}$-axis where ITO is prohibited by a $C_2$ symmetry. If the transition in $\alpha$-RuCl${}_3$ is indeed a direct transition between ITOs, then this feature in $k$ should be observable.

arXiv comment7 pages, 2 figures, 1 table

References in corpus (36)

• Anyons in an exactly solved model and beyond
• Mott Insulators in the Strong Spin-Orbit Coupling Limit: From Heisenberg to a Quantum Compass and Kitaev Models
• Kitaev-Heisenberg Model on Honeycomb Lattice: Possible Exotic Phases in Iridium Oxides $A_2$IrO${}_3$
• Majorana quantization and half-integer thermal quantum Hall effect in a Kitaev spin liquid
• Proximate Kitaev Quantum Spin Liquid Behaviour in α-RuCl${}_3$
• $\alpha$-RuCl3: a Spin-Orbit Assisted Mott Insulator on a Honeycomb Lattice
• Relevance of the Heisenberg-Kitaev model for the honeycomb lattice iridates A_2IrO_3
• Generic spin model for the honeycomb iridates beyond the Kitaev limit
• Spin waves and revised crystal structure of honeycomb iridate Na2IrO3
• On the Origin of Zigzag Magnetic Order in Iridium Oxide Na2IrO3
• The monoclinic crystal structure of $\alpha$-RuCl${}_3$ and the zigzag antiferromagnetic ground state
• Scattering Continuum and Possible Fractionalized Excitations in $\alpha$-RuCl${}_3$
• Magnetic order in $\alpha$-RuCl${}_3$: a honeycomb lattice quantum magnet with strong spin-orbit coupling
• Low-temperature crystal and magnetic structure of $\alpha$-RuCl3
• Evidence for a Field-induced Quantum Spin Liquid in $\alpha$-RuCl${}_3$
• Dynamics of a two-dimensional quantum spin liquid: signatures of emergent Majorana fermions and fluxes
• Kitaev magnetism in honeycomb RuCl3 with intermediate spin-orbit coupling
• A new spin-anisotropic harmonic honeycomb iridate
• Crystal structure and magnetism in $\alpha$-RuCl3: an ab-initio study
• Gapless Spin Excitations in the Field-Induced Quantum Spin Liquid Phase of alpha-RuCl3
• Anomalous thermal conductivity and magnetic torque response in the honeycomb magnet $\alpha$-RuCl${}_3$
• Field-induced quantum criticality in the Kitaev system $\alpha$-RuCl${}_3$
• Magnetization processes of zigzag states on the honeycomb lattice: Identifying spin models for $\alpha$-RuCl${}_3$ and Na${}_2$IrO${}_3$
• Spin-orbit excitations and electronic structure of the putative Kitaev magnet $\alpha$-RuCl${}_3$
• Topological Magnons in Kitaev Magnets at High Fields
• Observation of two types of anyons in the Kitaev honeycomb magnet
• Pseudo-Goldstone gaps and order-by-quantum-disorder in frustrated magnets
• Dirac and Chiral Quantum Spin Liquids on the Honeycomb Lattice in a Magnetic Field
• Electrical probes of the non-Abelian spin liquid in Kitaev materials
• Scale-invariant magnetic anisotropy in RuCl${}_3$ at high magnetic fields
• Resonant torsion magnetometry in anisotropic quantum materials
• Field-induced QCD${}_3$-Chern-Simons quantum criticalities in Kitaev materials
• Magnon dispersion and dynamic spin response in three-dimensional spin models for $\alpha$-RuCl${}_3$
• Magnetic anisotropy of the alkali iridate Na${}_2$IrO${}_3$ at high magnetic fields: evidence for strong ferromagnetic Kitaev correlations
• On the saw-tooth torque in anisotropic $j_{\mathrm{eff}}=1/2$ magnets: Application to $\alpha$-RuCl${}_3$
• Reentrant incommensurate order and anomalous magnetic torque in the Kitaev magnet $\beta$-${\text{Li}}_2{\text{IrO}}_3$

Cited by in corpus (10)

• Sign structure of thermal Hall conductivity for in-plane-field polarized Kitaev magnets
• Geometrical frustration versus Kitaev interactions in BaCo${}_2$(AsO${}_4$)${}_2$
• Topological magnons for thermal Hall transport in frustrated magnets with bond-dependent interactions
• Identification of a Kitaev Quantum Spin Liquid by Magnetic Field Angle Dependence
• Topological phase diagrams of in-plane field polarized Kitaev magnets
• Static and fluctuating zigzag order, and possible signatures of Kitaev physics, in torque measurements of $\alpha$-RuCl${}_3$
• Successive topological phase transitions in two distinct spin-flop phases on the honeycomb lattice
• Emergent Hyper-Magic Manifold in Twisted Kitaev Bilayers
• Field-Induced Ordered Phases in Anisotropic Spin-1/2 Kitaev Chains
• The field-angle anisotropy of proximate Kitaev systems under an in-plane magnetic field