Kitaev magnetism in honeycomb RuCl3 with intermediate spin-orbit coupling

Abstract

Intensive studies of the interplay between spin-orbit coupling (SOC) and electronic correlations in transition metal compounds have recently been undertaken. In particular, $j_{\mathrm{eff}}$ = 1/2 bands on a honeycomb lattice provide a pathway to realize Kitaev's exactly solvable spin model. However, since current wisdom requires strong atomic SOC to make $j_{\mathrm{eff}}=1/2$ bands, studies have been limited to iridium oxides. Contrary to this expectation, we demonstrate how Kitaev interactions arise in 4$d$-orbital honeycomb $\alpha$-RuCl${}_3$, despite having significantly weaker SOC than the iridium oxides, via assistance from electron correlations. A strong coupling spin model for these correlation-assisted $j_{\mathrm{eff}}$ = 1/2 bands is derived, in which large antiferromagnetic Kitaev interactions emerge along with ferromagnetic Heisenberg interactions. Our analyses suggest that the ground state is a zigzag-ordered phase lying close to the antiferromagnetic Kitaev spin liquid. Experimental implications for angle resolved photoemission spectroscopy, neutron scattering, and optical conductivities are discussed.

8 pages, 5 figures, Accepted in Phys. Rev. B Rapid communications

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Cited by in corpus (23)

• Models and Materials for Generalized Kitaev Magnetism
• Spin-wave excitations evidencing the Kitaev interaction in single crystalline $\alpha$-RuCl${}_3$
• Kitaev-Heisenberg Hamiltonian for High-Spin $d^7$ Mott Insulators
• Magnetization processes of zigzag states on the honeycomb lattice: Identifying spin models for $\alpha$-RuCl${}_3$ and Na${}_2$IrO${}_3$
• Microscopic mechanism for higher-spin Kitaev model
• Quantum anomalous Hall effect in ferromagnetic transition metal halides
• Magnetic anisotropy in the Kitaev model systems Na2IrO3 and RuCl3
• Theory of the field-revealed Kitaev spin liquid
• Electronic Structure of the Kitaev Material $\alpha$-${\text{RuCl}}_3$ Probed by Photoemission and Inverse Photoemission Spectroscopies
• Optically Driven Magnetic Phase Transition of Monolayer RuCl3
• Kitaev materials beyond iridates: order by quantum disorder and Weyl magnons in rare-earth double perovskites
• Identification of Magnetic Interactions and High-field Quantum Spin Liquid in $\alpha$-RuCl${}_3$
• Comprehensive study of the dynamics of a classical Kitaev spin liquid
• High-pressure magnetization and NMR studies on $\alpha$-RuCl${}_3$
• Electronic and phonon excitations in α-RuCl${}_3$
• Magnon damping in the zigzag phase of the Kitaev-Heisenberg-$\Gamma$ model on a honeycomb lattice
• Floquet engineering of Mott insulators with strong spin-orbit coupling
• Local nuclear and magnetic order in the two-dimensional spin glass, Mn${}_{0.5}$Fe${}_{0.5}$PS${}_3$
• Topological superconductivity in the extended Kitaev-Heisenberg model
• Extent of frustration in the classical Kitaev-$\Gamma$ model via bond anisotropy
• Interplay of magnetic field and trigonal distortion in the honeycomb $\Gamma$ model: Occurrence of a spin-flop phase
• Designer quantum matter in van der Waals heterostructures
• The field-angle anisotropy of proximate Kitaev systems under an in-plane magnetic field