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arXiv · 1904.01025

Kitaev honeycomb models in magnetic fields: Dynamical response and hidden symmetries

David A. S. Kaib·Stephen M. Winter·Roser Valenti
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Abstract

Motivated by recent reports of a field-induced intermediate phase (IP) in the antiferromagnetic honeycomb Kitaev model that may be a spin liquid whose nature is distinct from the Kitaev Z2 phase, we present a detailed numerical study on the nature and dynamical response (such as dynamical spin-structure factors and resonant inelastic x-ray scattering intensities) of this field-induced IP and neighboring phases in a family of Kitaev-based models related by hidden symmetries and duality transformations. We further show that the same field-induced IP can appear in models relevant for $α$-RuCl${_3}$, which exhibit a ferromagnetic Kitaev coupling and additional interactions. In $α$-RuCl${_3}$, the IP represents a new phase, that is likely independent from the putative field-induced (spin-liquid) phase recently reported from thermal Hall conductivity measurements.

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David A. S. Kaib, Stephen M. Winter, Roser Valenti. 2019-04-01. Kitaev honeycomb models in magnetic fields: Dynamical response and hidden symmetries. https://doi.org/10.1103/physrevb.100.144445

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