Signatures of Kitaev interactions in the van der Waals ferromagnet VI3

Abstract

Materials manifesting the Kitaev model, characterized by bond-dependent interactions on a honeycomb lattice, can host exotic phenomena like quantum spin liquid states and topological magnetic excitations. However, finding such materials remains a formidable challenge. Here, we report high-resolution inelastic neutron scattering measurements performed on VI3, a van der Waals ferromagnetic Mott insulator, covering a wide range of reciprocal space. Our measurements unveil highly anisotropic magnetic excitations in momentum space. Through a comprehensive comparative analysis of various models that incorporate diverse symmetry-allowed magnetic interactions, we find the observed excitations are well captured by a model with a large bond-dependent Kitaev interaction. These results not only help to understand the intriguing properties of VI3, such as the pronounced anomalous thermal Hall effects and strong pressure/structure dependence of magnetism, but also open a new avenue for exploring Kitaev physics.

17 pages, 4 figures

References in corpus (30)

• Mott Insulators in the Strong Spin-Orbit Coupling Limit: From Heisenberg to a Quantum Compass and Kitaev Models
• $\alpha$-RuCl3: a Spin-Orbit Assisted Mott Insulator on a Honeycomb Lattice
• Ferromagnetic van der Waals crystal VI3
• Kitaev Spin Liquid in 3d Transition Metal Compounds
• VI3 - a new layered ferromagnetic semiconductor
• Possible Kitaev Quantum Spin Liquid State in 2D Materials with S=3/2
• Microscopic mechanism for higher-spin Kitaev model
• Kitaev interactions in the Co honeycomb antiferromagnets Na${}_3$Co${}_2$SbO${}_6$ and Na${}_2$Co${}_2$TeO${}_6$
• Bulk properties of van-der-Waals hard ferromagnet VI3
• Magnetic field effect on topological spin excitations in CrI${}_3$
• Anomalous Thermal Hall Effect in an Insulating van der Waals Magnet VI3
• VI3: a 2D Ising ferromagnet
• Geometrical frustration versus Kitaev interactions in BaCo${}_2$(AsO${}_4$)${}_2$
• Excitations in the ordered and paramagnetic states of honeycomb magnet Na2Co2TeO6
• Hybridized quadrupolar excitations in the spin-anisotropic frustrated magnet FeI2
• Spin-1 Kitaev-Heisenberg model on a two-dimensional honeycomb lattice
• Spin-orbital entangled state and realization of Kitaev physics in 3d cobalt compounds: a progress report
• Magnetic anisotropy reversal driven by structural symmetry-breaking in monolayer α-RuCl3
• Bond-dependent anisotropy and magnon decay in cobalt-based Kitaev triangular antiferromagnet
• Tuning Magnetism in Layered Magnet VI${}_3$: A Theoretical Study
• Pressure-induced huge increase of Curie temperature of the van der Waals ferromagnet VI3
• Large orbital magnetic moment in VI3
• Ground-state phase diagram of spin-$S$ Kitaev-Heisenberg models
• Strain tunability of perpendicular magnetic anisotropy in van der Waals ferromagnets VI3
• Magnetic order and its interplay with structure phase transition in van der Waals ferromagnet VI${}_3$
• Magnetic anisotropy in van-der-Waals ferromagnet VI3
• Instabilities of heavy magnons in an anisotropic magnet
• Instabilities of spin-1 Kitaev spin liquid phase in presence of single-ion anisotropies
• Two-dimensional ferromagnetic spin-orbital excitations in the honeycomb VI${}_3$
• Terahertz Magnetic and Lattice Excitations in van der Waals Ferromagnet VI3

Cited by in corpus (7)

• Magnetic Anisotropy in Two-dimensional van der Waals Magnetic Materials and Their Heterostructures: Importance, Mechanisms, and Opportunities
• Intrinsic Spin Nernst Effect and Chiral Edge Modes in van der Waals Ferromagnetic Insulators: Dzyaloshinskii-Moriya vs. Kitaev Interactions
• Raman spectroscopy of anyons in generic Kitaev spin liquids
• Kitaev interactions in the van der Waals antiferromagnet VBr3
• Angular-Dependent Thermal Hall Effect in a Honeycomb Magnet: Disentangling Kitaev and Dzyaloshinskii-Moriya Interactions
• Chiral spin liquid in a generalized Kitaev honeycomb model with ${\mathbb{Z}}_4$ 1-form symmetry
• Sizable Ligand-Mediated Bond-Dependent Interactions in a Spin-1 Triangular Antiferromagnet NiI${}_2$