Dynamic fingerprint of fractionalized excitations in single-crystalline Cu${}_3$Zn(OH)${}_6$FBr

Abstract

Quantum spin liquid (QSL) represents a new class of condensed matter states characterized by the long-range many-body entanglement of topological orders. The most prominent feature of the elusive QSL state is the existence of fractionalized spin excitations. Subject to the strong quantum fluctuations, the spin-1/2 antiferromagnetic system on a kagome lattice is the promising candidate for hosting a QSL ground state, but the structurally ideal realization is rare. Here, we report Raman scattering on the single crystalline Cu${}_3$Zn(OH)${}_6$FBr, and confirm that the ideal kagome structure remains down to low temperatures without any lattice distortion by the angle-resolved polarized Raman responses and second-harmonic-generation measurements. Furthermore, at low temperatures the Raman scattering reveals a continuum of the spin excitations in Cu${}_3$Zn(OH)${}_6$FBr, in contrast to the sharp magnon peak in the ordered kagome antiferromagnet EuCu${}_3$(OH)${}_6$Cl${}_3$. Such magnetic Raman continuum, in particular, the substantial low-energy one-pair spinon excitation serves as strong evidence for fractionalized spin excitations in Cu${}_3$Zn(OH)${}_6$FBr.

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References in corpus (23)

• Spin Dynamics of the Spin-1/2 Kagome Lattice Antiferromagnet ZnCu_3(OH)_6Cl_2
• Inelastic Light Scattering From Correlated Electrons
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• Constraints on topological order in Mott Insulators
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• The range of non-Kitaev terms and fractional particles in RuCl${}_3$
• Symmetry Reduction in the Quantum Kagome Antiferromagnet Herbertsmithite
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• How to detect weak emergent broken-symmetries of the Kagome antiferromagnet from Raman spectroscopy
• Lattice dynamics in the spin-1/2 frustrated kagome compound herbertsmithite
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Cited by in corpus (21)

• Possible Dirac quantum spin liquid in a kagome quantum antiferromagnet YCu${}_3$(OH)${}_6$Br${}_2$[Br${}_x$(OH)${}_{1-x}$]
• Gapless Spin Liquid Behavior in A Kagome Heisenberg Antiferromagnet with Randomly Distributed Hexagons of Alternate Bonds
• Heat Transport in Herbertsmithite: Can a Quantum Spin Liquid Survive Disorder?
• Exploring Quantum Materials with Resonant Inelastic X-Ray Scattering
• From spin liquid to magnetic ordering in the anisotropic kagome Y-Kapellasite Y3Cu9(OH)19Cl8: a single crystal study
• Variational Monte Carlo Study of the 1/9 Magnetization Plateau in Kagome Antiferromagnets
• Freezing of the Lattice in the Kagome Lattice Heisenberg Antiferromagnet Zn-barlowite ZnCu${}_3$(OD)${}_6$FBr
• Magnetic ground states in kagome YCu${}_3$(OH)${}_6$[(Cl${}_x$Br${}_{1-x}$)${}_{3-y}$(OH)${}_y$]
• Emergence of the spin polarized domains in the kagome lattice Heisenberg antiferromagnet Zn-barlowite (Zn${}_{0.95}$Cu${}_{0.05}$)Cu${}_3$(OD)${}_6$FBr
• High energy spin excitations in the quantum spin liquid candidate Zn-barlowite probed by resonant inelastic x-ray scattering
• Fluctuating Fractionalized Spins in Quasi Two-dimensional Magnetic V0.85PS3
• Chemo-Structural Disorder in the kagomé spin $S$ = 1/2 systems ZnCu${}_3$(OH)${}_6$Cl${}_2$ and YCu${}_3$(OH)${}_6$Br${}_2$[Br${}_x$(OH)${}_{1-x}$]
• Nature of the 1/3 Magnetization Plateau in Spin-1/2 Kagome Antiferromagnets
• Recent progress in quantum spin liquids, fractional magnetization plateaus, and unconventional superconductivity in kagome lattices
• Spin excitations arising from anisotropic Dirac spinons in YCu${}_3$(OD)${}_6$Br${}_2$[Br${}_{0.33}$(OD)${}_{0.67}$]
• Raman spectroscopy of anyons in generic Kitaev spin liquids
• Exerting chemical pressure on the kagome lattice as frustration control in the kapellasite family $A$Cu${}_3$(OH)${}_{6+x}$(Cl,Br)${}_{3-x}$
• Artificial Gauge Field Engineered Excited-State Topology: Control of Dynamical Evolution of Localized Spinons
• Pressure-tuned spin chains in brochantite, Cu${}_4$SO${}_4$(OH)${}_6$
• Dynamical spin correlations in kagome antiferromagnets: comparison of Abrikosov fermion and Schwinger boson approaches beyond mean field
• Local probe investigation of the spin dynamics in the kagome and inter-layers of orthorhombic barlowite Cu${}_4$(OD)${}_6$FBr: ${}^{79}$Br and ${}^{63}$Cu NQR study