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arXiv · 1905.11408

Magnetic Field Induced Competing Phases in Spin-Orbital Entangled Kitaev Magnets

Li Ern Chern·Ryui Kaneko·Hyun-Yong Lee·Yong Baek Kim
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Abstract

There has been a great interest in magnetic field induced quantum spin liquids in Kitaev magnets after the discovery of neutron scattering continuum and half quantized thermal Hall conductivity in the material $\alpha$-RuCl$_3$. In this work, we provide a semiclassical analysis of the relevant theoretical models on large system sizes, and compare the results to previous studies on quantum models with small system sizes. We find a series of competing magnetic orders with fairly large unit cells at intermediate magnetic fields, which are most likely missed by previous approaches. We show that quantum fluctuations are typically strong in these large unit cell orders, while their magnetic excitations may resemble a scattering continuum and give rise to a large thermal Hall conductivity. Our work provides an important basis for a thorough investigation of emergent spin liquids and competing phases in Kitaev magnets.

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Li Ern Chern, Ryui Kaneko, Hyun-Yong Lee, Yong Baek Kim. 2019-05-27. Magnetic Field Induced Competing Phases in Spin-Orbital Entangled Kitaev Magnets. https://doi.org/10.1103/physrevresearch.2.013014

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