Polarization-dependent magnetic properties of periodically driven $\alpha$-RuCl${}_3$

Abstract

We study magnetic properties of a periodically driven Mott insulator with strong spin-orbit coupling and show some properties characteristic of linearly polarized light. We consider a $t_{2g}$-orbital Hubbard model driven by circularly or linearly polarized light with strong spin-orbit coupling and derive its effective Hamiltonian in the strong-interaction limit for a high-frequency case. We show that linearly polarized light can change not only the magnitudes and signs of the exchange interactions, but also their bond anisotropy even without the bond-anisotropic hopping integrals. Because of this property, the honeycomb-network spin system could be transformed into weakly coupled zigzag or step spin chains for the light field polarized along the $b$- or $a$-axis, respectively. Then, analyzing how the light fields affect several magnetic states in a mean-field approximation, we show that linearly polarized light can change the relative stability of the competing magnetic states, whereas such a change is absent for circularly polarized light. We also analyze the effects of both the bond anisotropy of nearest-neighbor hopping integrals and a third-neighbor hopping integral on the magnetic states and show that the results obtained in a simple model, in which the bond-averaged nearest-neighbor hopping integrals are considered, remain qualitatively unchanged except for the stability of zigzag states in the non-driven case and the degeneracy lifting of the zigzag or stripy states.

24 pages, 15 figures, 1 table; published

References in corpus (8)

• Mott Insulators in the Strong Spin-Orbit Coupling Limit: From Heisenberg to a Quantum Compass and Kitaev Models
• Novel Jeff = 1/2 Mott State Induced by Relativistic Spin-Orbit Coupling in Sr2IrO4
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• Kitaev magnetism in honeycomb RuCl3 with intermediate spin-orbit coupling
• Hidden symmetries of the extended Kitaev-Heisenberg model: Implications for honeycomb lattice iridates A2IrO3
• Magnetization processes of zigzag states on the honeycomb lattice: Identifying spin models for $\alpha$-RuCl${}_3$ and Na${}_2$IrO${}_3$
• Kitaev-like honeycomb magnets: Global phase behavior and emergent effective models
• Floquet engineering of Mott insulators with strong spin-orbit coupling

Cited by in corpus (5)

• Symmetry analysis of light-induced magnetic interactions via Floquet engineering
• Symmetry-protected difference between spin Hall and anomalous Hall effects of a periodically driven multiorbital metal
• From linear to circular polarized light -- Floquet engineering in Kitaev-Heisenberg materials with Lissajous figures
• Scalar spin chirality induced by a circularly polarized electric field in a classical kagome magnet
• Photoinduced Pseudospin Polarization in a Three-Orbital Hubbard Model