Emergent orbital magnetization in Kitaev quantum magnets

Abstract

Unambiguous identification of the Kitaev quantum spin liquid (QSL) in materials remains a huge challenge despite many encouraging signs from various measurements. To facilitate the experimental detection of the Kitaev QSL, here we propose to use remnant charge response in Mott insulators hosting QSL to identify the key signatures of QSL. We predict an emergent orbital magnetization in a Kitaev system in an external magnetic field. The direction of the orbital magnetization can be flipped by rotating the external magnetic field in the honeycomb plane. The orbital magnetization is demonstrated explicitly through a detailed microscopic analysis of the multiorbital Hubbard-Kanamori Hamiltonian and also supported by a phenomenological picture. We first derive the localized electrical loop current operator in terms of the spin degrees of freedom. Thereafter, utilizing the Majorana representation, we estimate the loop currents in the ground state of the chiral Kitaev QSL state, and obtain the consequent current textures, which are responsible for the emergent orbital magnetization. Finally, we discuss the possible experimental techniques to visualize the orbital magnetization which can be considered as the signatures of the underlying excitations.

Updated version

References in corpus (18)

• The electronic properties of graphene
• Mott Insulators in the Strong Spin-Orbit Coupling Limit: From Heisenberg to a Quantum Compass and Kitaev Models
• Models and Materials for Generalized Kitaev Magnetism
• On the Origin of Zigzag Magnetic Order in Iridium Oxide Na2IrO3
• Magnetic order in the pseudogap phase of high-$T_C$ superconductors
• Magnetic order in $\alpha$-RuCl${}_3$: a honeycomb lattice quantum magnet with strong spin-orbit coupling
• Quantum spin Hall effect in a transition metal oxide Na2IrO3
• Exact results for spin dynamics and fractionization in the Kitaev Model
• Kitaev magnetism in honeycomb RuCl3 with intermediate spin-orbit coupling
• Genons, twist defects, and projective non-Abelian braiding statistics
• Electronic Orbital Currents and Polarization in Mott Insulators
• Robustness of edge states in graphene quantum dots
• Zero modes and the edge states of the honeycomb lattice
• Physical states and finite-size effects in Kitaev's honeycomb model: Bond disorder, spin excitations, and NMR lineshape
• Electronic Structure of the Kitaev Material $\alpha$-${\text{RuCl}}_3$ Probed by Photoemission and Inverse Photoemission Spectroscopies
• Phase diagram and spin correlations of the Kitaev-Heisenberg model: Importance of quantum effects
• Floquet engineering of Mott insulators with strong spin-orbit coupling
• Designing spin and orbital exchange Hamiltonians with ultrashort electric field transients

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• Multipolar multiferroics in $4d^2$/$5d^2$ Mott insulators
• A primer on Kitaev Model: Basic aspects, material realization, and recent experiments
• Electric polarization near vortices in the extended Kitaev model
• Deciphering competing interactions of Kitaev-Heisenberg-$\Gamma$ system in clusters: part I -- static properties
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