Dirac Magnons in a Honeycomb Lattice Quantum XY Magnet CoTiO 3

Yuan, Bo; Khait, Ilia; Shu, Guo-Jiun; Chou, F. C.; Stone, M. B.; Clancy, J. P.; Paramekanti, Arun; Kim, Young-June

doi:10.1103/PhysRevX.10.011062

Title: Dirac Magnons in a Honeycomb Lattice Quantum $XY$ Magnet ${CoTiO}_{3}$

Abstract

The discovery of massless Dirac electrons in graphene and topological Dirac-Weyl materials has prompted a broad search for bosonic analogues of such Dirac particles. Recent experiments have found evidence for Dirac magnons above an Ising-like ferromagnetic ground state in a two-dimensional (2D) kagome lattice magnet and in the van der Waals layered honeycomb crystal CrI₃, and in a 3D Heisenberg magnet Cu₃TeO₆. Here, we report our inelastic neutron scattering investigation on a large single crystal of a stacked honeycomb lattice magnet CoTiO₃, which is part of a broad family of ilmenite materials. The magnetically ordered ground state of CoTiO₃ features ferromagnetic layers of Co²⁺, stacked antiferromagnetically along the c axis. The magnon dispersion relation is described very well with a simple magnetic Hamiltonian with strong easy-plane exchange anisotropy. Importantly, a magnon Dirac cone is found along the edge of the 3D Brillouin zone. Our results establish CoTiO₃ as a model pseudospin-1/2 material to study interacting Dirac bosons in a 3D quantum XY magnet.

Authors:

; Khait, Ilia; Shu, Guo-Jiun;

;

; Paramekanti, Arun;

Publication Date:: 2020-03-12

Research Org.:: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Sponsoring Org.:: USDOE Office of Science (SC); Ministry of Education in Taiwan; Natural Science and Engineering Research Council (NSERC); Ministry of Science and Technology (MOST)

OSTI Identifier:: 1604508

Alternate Identifier(s):: OSTI ID: 1666019

Grant/Contract Number:: AC05-00OR22725; 8-2622-8-002-016; 06-2119-M-002-035-MY3; 108L900903

Resource Type:: Published Article

Journal Name:: Physical Review. X

Additional Journal Information:: Journal Name: Physical Review. X Journal Volume: 10 Journal Issue: 1; Journal ID: ISSN 2160-3308

Publisher:: American Physical Society (APS)

Country of Publication:: United States

Language:: English

Subject:: 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; Magnons; symmetry protected topological states; magnetic insulators; inelastic neutron scattering

Citation Formats


                    Yuan, Bo, Khait, Ilia, Shu, Guo-Jiun, Chou, F. C., Stone, M. B., Clancy, J. P., Paramekanti, Arun, and Kim, Young-June. Dirac Magnons in a Honeycomb Lattice Quantum XY Magnet CoTiO 3.  United States: N. p., 2020. 
Web.  doi:10.1103/PhysRevX.10.011062.

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                    Yuan, Bo, Khait, Ilia, Shu, Guo-Jiun, Chou, F. C., Stone, M. B., Clancy, J. P., Paramekanti, Arun, & Kim, Young-June. Dirac Magnons in a Honeycomb Lattice Quantum XY Magnet CoTiO 3.  United States.  https://doi.org/10.1103/PhysRevX.10.011062

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                    Yuan, Bo, Khait, Ilia, Shu, Guo-Jiun, Chou, F. C., Stone, M. B., Clancy, J. P., Paramekanti, Arun, and Kim, Young-June. Thu .  
"Dirac Magnons in a Honeycomb Lattice Quantum XY Magnet CoTiO 3".  United States.  https://doi.org/10.1103/PhysRevX.10.011062.

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@article{osti_1604508,

  title        = {Dirac Magnons in a Honeycomb Lattice Quantum XY Magnet CoTiO 3},

  author       = {Yuan, Bo and Khait, Ilia and Shu, Guo-Jiun and Chou, F. C. and Stone, M. B. and Clancy, J. P. and Paramekanti, Arun and Kim, Young-June},

  abstractNote = {The discovery of massless Dirac electrons in graphene and topological Dirac-Weyl materials has prompted a broad search for bosonic analogues of such Dirac particles. Recent experiments have found evidence for Dirac magnons above an Ising-like ferromagnetic ground state in a two-dimensional (2D) kagome lattice magnet and in the van der Waals layered honeycomb crystal CrI3, and in a 3D Heisenberg magnet Cu3TeO6. Here, we report our inelastic neutron scattering investigation on a large single crystal of a stacked honeycomb lattice magnet CoTiO3, which is part of a broad family of ilmenite materials. The magnetically ordered ground state of CoTiO3 features ferromagnetic layers of Co2+, stacked antiferromagnetically along the c axis. The magnon dispersion relation is described very well with a simple magnetic Hamiltonian with strong easy-plane exchange anisotropy. Importantly, a magnon Dirac cone is found along the edge of the 3D Brillouin zone. Our results establish CoTiO3 as a model pseudospin-1/2 material to study interacting Dirac bosons in a 3D quantum XY magnet.},

  doi          = {10.1103/PhysRevX.10.011062},

  journal      = {Physical Review. X},

  number       = 1,

  volume       = 10,

  place        = {United States},

  year         = {2020},

  month        = {3}

}

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Cited by: 51 works

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Figures / Tables:

FIG. 1: (a) Structure of CoTiO₃. A nonprimitive hexagonal unit cell, which is used to describe our data, is indicated by solid black lines. (b) Magnetic structure of the Co²⁺ sublattice. The Co²⁺ magnetic moments (shown by green arrows) order ferromagnetically within each honeycomb plane and antiferromagnetically along the cmore »

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Title: Dirac Magnons in a Honeycomb Lattice Quantum XY Magnet CoTiO 3

Abstract

Citation Formats

Figures / Tables:

Experimental observation of the quantum Hall effect and Berry's phase in graphene journal, November 2005

Substrate-induced bandgap opening in epitaxial graphene journal, September 2007

Pseudospin exchange interactions in d 7 cobalt compounds: Possible realization of the Kitaev model journal, January 2018

Dirac materials journal, January 2014

Electronic properties of graphene in a strong magnetic field journal, November 2011

Kitaev-Heisenberg Hamiltonian for high-spin d 7 Mott insulators journal, January 2018

Topological photonics journal, March 2019

Electric and magnetic properties of titanium-cobalt-oxide single crystals produced by floating zone melting with light heating journal, August 2017

Unconventional superconductivity in magic-angle graphene superlattices journal, March 2018

Discovery of coexisting Dirac and triply degenerate magnons in a three-dimensional antiferromagnet journal, July 2018

Neutron scattering study of magnetic excitations in oblique easy-axis antiferromagnet FeTiO 3 journal, December 1986

Weyl magnons in breathing pyrochlore antiferromagnets journal, September 2016

Coherent and incoherent coupling dynamics in a two-dimensional atomic crystal embedded in a plasmon-induced magnetic resonator journal, January 2020

Two Topologically Distinct Dirac-Line Semimetal Phases and Topological Phase Transitions in Rhombohedrally Stacked Honeycomb Lattices journal, January 2018

Defect Scattering in Graphene journal, June 2009

Excitations in KCoF 3 . II. Theoretical journal, October 1971

Magnetic anisotropies in MTiO3 (M = Co, Ni) journal, January 1980

Double-Weyl Phonons in Transition-Metal Monosilicides journal, January 2018

Observation of Double Weyl Phonons in Parity-Breaking FeSi journal, July 2018

Edge states in topological magnon insulators journal, July 2014

A first theoretical realization of honeycomb topological magnon insulator journal, July 2016

Strain Engineering of Graphene’s Electronic Structure journal, July 2009

Classification of topological quantum matter with symmetries journal, August 2016

Recipe for Dirac Phonon States with a Quantized Valley Berry Phase in Two-Dimensional Hexagonal Lattices journal, November 2018

Topological photonics journal, October 2014

Renormalization of Large-Wave-Vector Magnons in Ferromagnetic Cr Br 3 Studied by Inelastic Neutron Scattering: Spin-Wave Correlation Effects journal, October 1971

Evolution of magnetic Dirac bosons in a honeycomb lattice journal, January 2018

Topological Spin Excitations in Honeycomb Ferromagnet CrI 3 journal, November 2018

Single-ion properties of the S eff = 1 2 XY antiferromagnetic pyrochlores Na A ′ Co 2 F 7 ( A ′ = Ca 2 + , Sr 2 + ) journal, April 2017

Crystal structure and magnetic properties of CoTiO3 journal, March 1964

The electronic properties of graphene journal, January 2009

Metal to Insulator Transition in Epitaxial Graphene Induced by Molecular Doping journal, August 2008

Linear spin wave theory for single-Q incommensurate magnetic structures journal, March 2015

Chiral tunnelling and the Klein paradox in graphene journal, August 2006

Modeling disorder in graphene journal, March 2008

Topological spin excitations in a three-dimensional antiferromagnet journal, July 2018

Energy gaps and a zero-field quantum Hall effect in graphene by strain engineering journal, September 2009

Theory of the Magnetic Properties of the Ilmenites M Ti O 3 journal, December 1967

Dirac Magnons in Honeycomb Ferromagnets journal, January 2018

Magnon Dirac materials journal, August 2016

Epitaxial growth of NiTiO3 with a distorted ilmenite structure journal, June 2012

Two-dimensional gas of massless Dirac fermions in graphene journal, November 2005

Title: Dirac Magnons in a Honeycomb Lattice Quantum $XY$ Magnet ${CoTiO}_{3}$

Experimental observation of the quantum Hall effect and Berry's phase in graphene
journal, November 2005

Substrate-induced bandgap opening in epitaxial graphene
journal, September 2007

Pseudospin exchange interactions in $d^{7}$ cobalt compounds: Possible realization of the Kitaev model
journal, January 2018

Dirac materials
journal, January 2014

Electronic properties of graphene in a strong magnetic field
journal, November 2011

Kitaev-Heisenberg Hamiltonian for high-spin $d^{7}$ Mott insulators
journal, January 2018

Topological photonics
journal, March 2019

Electric and magnetic properties of titanium-cobalt-oxide single crystals produced by floating zone melting with light heating
journal, August 2017

Unconventional superconductivity in magic-angle graphene superlattices
journal, March 2018

Discovery of coexisting Dirac and triply degenerate magnons in a three-dimensional antiferromagnet
journal, July 2018

Neutron scattering study of magnetic excitations in oblique easy-axis antiferromagnet FeTiO ₃
journal, December 1986

Weyl magnons in breathing pyrochlore antiferromagnets
journal, September 2016

Coherent and incoherent coupling dynamics in a two-dimensional atomic crystal embedded in a plasmon-induced magnetic resonator
journal, January 2020

Two Topologically Distinct Dirac-Line Semimetal Phases and Topological Phase Transitions in Rhombohedrally Stacked Honeycomb Lattices
journal, January 2018

Defect Scattering in Graphene
journal, June 2009

Excitations in KCoF ₃ . II. Theoretical
journal, October 1971

Magnetic anisotropies in MTiO3 (M = Co, Ni)
journal, January 1980

Double-Weyl Phonons in Transition-Metal Monosilicides
journal, January 2018

Observation of Double Weyl Phonons in Parity-Breaking FeSi
journal, July 2018

Edge states in topological magnon insulators
journal, July 2014

A first theoretical realization of honeycomb topological magnon insulator
journal, July 2016

Strain Engineering of Graphene’s Electronic Structure
journal, July 2009

Classification of topological quantum matter with symmetries
journal, August 2016

Recipe for Dirac Phonon States with a Quantized Valley Berry Phase in Two-Dimensional Hexagonal Lattices
journal, November 2018

Topological photonics
journal, October 2014

Renormalization of Large-Wave-Vector Magnons in Ferromagnetic Cr ${Br}_{3}$ Studied by Inelastic Neutron Scattering: Spin-Wave Correlation Effects
journal, October 1971

Evolution of magnetic Dirac bosons in a honeycomb lattice
journal, January 2018

Topological Spin Excitations in Honeycomb Ferromagnet ${CrI}_{3}$
journal, November 2018

Single-ion properties of the $S_{eff}$ = $\frac{1}{2}$ XY antiferromagnetic pyrochlores $Na A^{'} {Co}_{2} F_{7}$ ( $A^{'} = {Ca}^{2 +}, {Sr}^{2 +}$ )
journal, April 2017

Crystal structure and magnetic properties of CoTiO3
journal, March 1964

The electronic properties of graphene
journal, January 2009

Metal to Insulator Transition in Epitaxial Graphene Induced by Molecular Doping
journal, August 2008

Linear spin wave theory for single-Q incommensurate magnetic structures
journal, March 2015

Chiral tunnelling and the Klein paradox in graphene
journal, August 2006

Modeling disorder in graphene
journal, March 2008

Topological spin excitations in a three-dimensional antiferromagnet
journal, July 2018

Energy gaps and a zero-field quantum Hall effect in graphene by strain engineering
journal, September 2009

Theory of the Magnetic Properties of the Ilmenites $M Ti O_{3}$
journal, December 1967

Dirac Magnons in Honeycomb Ferromagnets
journal, January 2018

Magnon Dirac materials
journal, August 2016

Epitaxial growth of NiTiO3 with a distorted ilmenite structure
journal, June 2012

Two-dimensional gas of massless Dirac fermions in graphene
journal, November 2005