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Title: Concept and realization of Kitaev quantum spin liquids

Abstract

The Kitaev model is an exactly solvable S = 1/2 spin model on a 2D honeycomb lattice, in which the spins fractionalize into Majorana fermions and form a topological quantum spin liquid (QSL) in the ground state. Several complex iridium oxides, as well as α-RuCl 3, are magnetic insulators with a honeycomb structure, and it was noticed that they accommodate essential ingredients of the Kitaev model owing to the interplay of electron correlation and spin–orbit coupling. This has led to a race to realize the Kitaev QSL and detect signatures of Majorana fermions. We summarize the theoretical background of the Kitaev QSL ground state and its realization using spin–orbital entangled J eff = 1/2 moments. We provide an overview of candidate materials and their electronic and magnetic properties, including Na 2IrO 3, α-Li 2IrO 3, β-Li 2IrO 3, γ-Li 2IrO 3, α-RuCl 3 and H 3LiIr 2O 6. Lastly, we discuss experiments showing that H 3LiIr 2O 6 and α-RuCl 3 in an applied magnetic field exhibit signatures of the QSL state and that α-RuCl 3 has unusual magnetic excitations and thermal transport properties consistent with spin fractionalization.

Authors:
ORCiD logo [1];  [2];  [2];  [3]; ORCiD logo [4]
  1. Max Planck Institute for Solid State Research, Stuttgart (Germany); Univ. of Stuttgart, Stuttgart (Germany); The Univ. of Tokyo, Tokyo (Japan)
  2. Max Planck Institute for Solid State Research, Stuttgart (Germany); Univ. of Stuttgart, Stuttgart (Germany)
  3. Max Planck Institute for Solid State Research, Stuttgart (Germany)
  4. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1509555
Grant/Contract Number:  
AC05-00OR22725
Resource Type:
Accepted Manuscript
Journal Name:
Nature Reviews Physics
Additional Journal Information:
Journal Volume: 1; Journal Issue: 4; Journal ID: ISSN 2522-5820
Publisher:
Springer Nature
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS

Citation Formats

Takagi, Hidenori, Takayama, Tomohiro, Jackeli, George, Khaliullin, Giniyat, and Nagler, Stephen E. Concept and realization of Kitaev quantum spin liquids. United States: N. p., 2019. Web. doi:10.1038/s42254-019-0038-2.
Takagi, Hidenori, Takayama, Tomohiro, Jackeli, George, Khaliullin, Giniyat, & Nagler, Stephen E. Concept and realization of Kitaev quantum spin liquids. United States. doi:10.1038/s42254-019-0038-2.
Takagi, Hidenori, Takayama, Tomohiro, Jackeli, George, Khaliullin, Giniyat, and Nagler, Stephen E. Mon . "Concept and realization of Kitaev quantum spin liquids". United States. doi:10.1038/s42254-019-0038-2.
@article{osti_1509555,
title = {Concept and realization of Kitaev quantum spin liquids},
author = {Takagi, Hidenori and Takayama, Tomohiro and Jackeli, George and Khaliullin, Giniyat and Nagler, Stephen E.},
abstractNote = {The Kitaev model is an exactly solvable S = 1/2 spin model on a 2D honeycomb lattice, in which the spins fractionalize into Majorana fermions and form a topological quantum spin liquid (QSL) in the ground state. Several complex iridium oxides, as well as α-RuCl3, are magnetic insulators with a honeycomb structure, and it was noticed that they accommodate essential ingredients of the Kitaev model owing to the interplay of electron correlation and spin–orbit coupling. This has led to a race to realize the Kitaev QSL and detect signatures of Majorana fermions. We summarize the theoretical background of the Kitaev QSL ground state and its realization using spin–orbital entangled Jeff = 1/2 moments. We provide an overview of candidate materials and their electronic and magnetic properties, including Na2IrO3, α-Li2IrO3, β-Li2IrO3, γ-Li2IrO3, α-RuCl3 and H3LiIr2O6. Lastly, we discuss experiments showing that H3LiIr2O6 and α-RuCl3 in an applied magnetic field exhibit signatures of the QSL state and that α-RuCl3 has unusual magnetic excitations and thermal transport properties consistent with spin fractionalization.},
doi = {10.1038/s42254-019-0038-2},
journal = {Nature Reviews Physics},
number = 4,
volume = 1,
place = {United States},
year = {2019},
month = {3}
}

Journal Article:
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    Works referencing / citing this record:

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