Theory of the Kitaev model in a [111] magnetic field

Abstract

Recent numerical studies indicate that the antiferromagnetic Kitaev honeycomb lattice model undergoes a magnetic-field-induced quantum phase transition into a new spin-liquid phase. This intermediate-field phase has been previously characterized as a gapless spin liquid. By implementing a recently developed variational approach based on the exact fractionalized excitations of the zero-field model, we demonstrate that the field-induced spin liquid is gapped and belongs to Kitaev's 16-fold way. Specifically, the low-field non-Abelian liquid with Chern number $C=\pm 1$ transitions into an Abelian liquid with $C=\pm 4$. The critical field and the field-dependent behaviors of key physical quantities are in good quantitative agreement with published numerical results. Furthermore, we derive an effective field theory for the field-induced critical point which readily explains the ostensibly gapless nature of the intermediate-field spin liquid.

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Cited by in corpus (10)

• Non-Abelian Floquet Spin Liquids in a Digital Rydberg Simulator
• Magnetic anisotropy reversal driven by structural symmetry-breaking in monolayer α-RuCl3
• Dynamics of visons and thermal Hall effect in perturbed Kitaev models
• Nature of visons in the perturbed ferromagnetic and antiferromagnetic Kitaev honeycomb models
• Anyon dynamics in field-driven phases of the anisotropic Kitaev model
• Fermionic approach to variational quantum simulation of Kitaev spin models
• Thermal Hall conductivity near field-suppressed magnetic order in a Kitaev-Heisenberg model
• Dynamic structure factor of the antiferromagnetic Kitaev model in large magnetic fields
• Kitaev honeycomb antiferromagnet in a field: quantum phase diagram for general spin
• Emergent Hyper-Magic Manifold in Twisted Kitaev Bilayers