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arXiv · 1804.06811

Dynamical and Topological Properties of the Kitaev Model in a [111] Magnetic Field

Matthias Gohlke·Roderich Moessner·Frank Pollmann
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Abstract

The Kitaev model exhibits a Quantum Spin Liquid hosting emergent fractionalized excitations. We study the Kitaev model on the honeycomb lattice coupled to a magnetic field along the [111] axis. Utilizing large scale matrix product based numerical models, we confirm three phases with transitions at different field strengths depending on the sign of the Kitaev exchange: a non-abelian topological phase at low fields, an enigmatic intermediate regime only present for antiferromagnetic Kitaev exchange, and a field-polarized phase. For the topological phase, we numerically observe the expected cubic scaling of the gap and extract the quantum dimension of the non-Abelian anyons. Furthermore, we investigate dynamical signatures of the topological and the field-polarized phase using a matrix product operator based time evolution method.

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Matthias Gohlke, Roderich Moessner, Frank Pollmann. 2018-12-05. Dynamical and Topological Properties of the Kitaev Model in a [111] Magnetic Field. https://doi.org/10.1103/physrevb.98.014418

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