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arXiv · 2412.09310

Ferrimagnetic Kitaev spin liquids in mixed spin 1/2 spin 3/2 honeycomb magnets

Willian Natori·Yang Yang·Hui-Ke Jin·Johannes Knolle·Natalia B. Perkins
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Abstract

We explore the potential experimental realization of the mixed-spin Kitaev model in materials such as Zr$_{0.5}$Ru$_{0.5}$Cl$_3$, where spin-1/2 and spin-3/2 ions occupy distinct sublattices of a honeycomb lattice. By developing a superexchange theory specifically for this mixed-spin system, we identify the conditions under which dominant Kitaev-like interactions emerge. Focusing on the limiting case of pure Kitaev coupling with single-ion anisotropy, we employ a combination of superexchange theory, parton mean-field theory, and density matrix renormalization group (DMRG) simulations. We establish a comprehensive ground-state phase diagram identifying four distinct quantum spin liquid phases. Our findings highlight the importance of spin-orbital couplings and quadrupolar order parameters in stabilizing exotic phases, providing a foundation for exploring mixed-spin Kitaev magnets.

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Willian Natori, Yang Yang, Hui-Ke Jin, Johannes Knolle, Natalia B. Perkins. 2024-12-12. Ferrimagnetic Kitaev spin liquids in mixed spin 1/2 spin 3/2 honeycomb magnets. https://arxiv.org/abs/2412.09310

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