Spin-Liquid--to--Spin-Liquid Transition in Kitaev Magnets Driven by Fractionalization

Abstract

While phase transitions between magnetic analogs of three states of matter --- a long-range ordered state, paramagnet, and spin liquid --- have been extensively studied, the possibility of "liquid-liquid" transitions, namely, between different spin liquids, remains elusive. By introducing the additional Ising coupling into the honeycomb Kitaev model with bond asymmetry, we discover that the Kitaev spin liquid turns into a spin-nematic quantum paramagnet before a magnetic order is established by the Ising coupling. The quantum phase transition between the two liquid states accompanies a topological change driven by fractionalized excitations, the $Z_2$ gauge fluxes, and is of first order. At finite temperatures, this yields a persisting first-order transition line that terminates at a critical point located deep inside the regime where quantum spins are fractionalized. It is suggested that similar transitions may occur in other perturbed Kitaev magnets with bond asymmetry.

8 pages, 6 figures

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Cited by in corpus (15)

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• Non-Kitaev spin liquids in Kitaev materials
• Topological Nematic Phase Transition in Kitaev Magnets Under Applied Magnetic Fields
• Majorana stripe order on the surface of a three-dimensional topological insulator
• Confinement transition in a Kitaev-like honeycomb model with bond anisotropy
• Quantum phase transition between spin liquid and spin nematics in spin-1 Kitaev honeycomb model
• Thermal Pure States for Systems with Antiunitary Symmetries and Their Tensor Network Representations
• Majorana Fermion Mean-Field Theories of Kitaev Quantum Spin Liquids
• Nature of Topological Phase Transition of Kitaev Quantum Spin Liquids
• String order parameters for symmetry fractionalization in an enriched toric code
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• Real-time control of non-Abelian anyons in Kitaev spin liquid under energy dissipation
• Real-space spectral simulation of quantum spin models: Application to generalized Kitaev models