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Theory of the field-revealed Kitaev spin liquid.

ABSTRACT: Elementary excitations in entangled states such as quantum spin liquids may exhibit exotic statistics different from those obeyed by fundamental bosons and fermions. Non-Abelian anyons exist in a Kitaev spin liquid-the ground state of an exactly solvable model. A smoking-gun signature of these excitations, namely a half-integer quantized thermal Hall conductivity, was recently reported in ?-RuCl3. While fascinating, a microscopic theory for this phenomenon remains elusive because the pure Kitaev model cannot display this effect in an intermediate magnetic field. Here we present a microscopic theory of the Kitaev spin liquid emerging between the low- and high-field states. Essential to this result is an antiferromagnetic off-diagonal symmetric interaction which allows the Kitaev spin liquid to protrude from the ferromagnetic Kitaev limit under a magnetic field. This generic model displays a strong field anisotropy, and we predict a wide spin liquid regime when the field is perpendicular to the honeycomb plane.

SUBMITTER: Gordon JS

PROVIDER: S-EPMC6554414 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature

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Theory of the field-revealed Kitaev spin liquid.

Gordon Jacob S JS Catuneanu Andrei A Sørensen Erik S ES Kee Hae-Young HY

Nature communications 20190606 1

Elementary excitations in entangled states such as quantum spin liquids may exhibit exotic statistics different from those obeyed by fundamental bosons and fermions. Non-Abelian anyons exist in a Kitaev spin liquid-the ground state of an exactly solvable model. A smoking-gun signature of these excitations, namely a half-integer quantized thermal Hall conductivity, was recently reported in α-RuCl<sub>3</sub>. While fascinating, a microscopic theory for this phenomenon remains elusive because the ...[more]

PMID: 31171777

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