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DOE OSTI · 2901508

Strong Kitaev Interaction in BaCo 2⁢ (AsO 4 ) 2

Maksimov, Pavel A. [Joint Institute for Nuclear Research, Moscow region (Russia); M. N. Mikheev Institute of Metal Physics of Ural Branch of Russian Academy of Sciences, Yekaterinburg (Russia)] (ORCID:0000000192647888)·Jiang, Shengtao [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States); Stanford University, CA (United States)] (ORCID:0000000329870846)·Regnault, L. P. [Institut Laue Langevin (France); CEA-Grenoble (France)] (ORCID:000000024786299X)·Chernyshev, A. L. [University of California, Irvine, CA (United States)] (ORCID:000000030965568X)
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Abstract

The inelastic neutron scattering results and their analysis unequivocally point to a dominant Kitaev interaction in the honeycomb-lattice cobaltate BaCo 2 ⁢(AsO 4 ) 2 . Our anisotropic-exchange model closely describes all available neutron scattering data in the material’s field-polarized phase. Furthermore, the density-matrix renormalization group results for our model are in close accord with the unusual double-zigzag magnetic order and the low in-plane saturation field of BaCo 2 ⁢(AsO 4 ) 2 .

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75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYAntiferromagnetismAntiferromagnetsDensity matrix methodsDensity matrix renormalization groupExchange interactionFrustrated magnetismHolstein-Primakoff methodInelastic neutron scatteringInsulatorsKitaev materialsKitaev modelKitaev-Heisenberg modelLinear spin wave theoryMagnetic insulatorsMagnetic interactionsMagnetic orderMagnetic phase transitionsMagnetic systemsMagnetismMagnonsMany-body techniquesMott insulatorsNeutron scatteringNoncollinear magnetsPhase diagramsQuantum spin liquidSpin lattice modelsSpin liquidSpin wave theorySpin-orbit couplingXY modelantiferromagnetismexchange interactionfrustrated magnetisminsulatorsmagnetic interactionsmagnonsneutron scatteringspin liquidspin wave theory

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Maksimov, Pavel A. [Joint Institute for Nuclear Research, Moscow region (Russia); M. N. Mikheev Institute of Metal Physics of Ural Branch of Russian Academy of Sciences, Yekaterinburg (Russia)] (ORCID:0000000192647888), Jiang, Shengtao [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States); Stanford University, CA (United States)] (ORCID:0000000329870846), Regnault, L. P. [Institut Laue Langevin (France); CEA-Grenoble (France)] (ORCID:000000024786299X), Chernyshev, A. L. [University of California, Irvine, CA (United States)] (ORCID:000000030965568X). 2025-08-07. Strong Kitaev Interaction in BaCo 2⁢ (AsO 4 ) 2. https://doi.org/10.1103/k1gq-k8m7

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75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY subjectFrustrated magnetism subjectMagnetism subjectQuantum spin liquid subjectinsulators subjectneutron scattering subject

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