Disorder-induced broadening of the spin waves in a triangular-lattice quantum-spin-liquid candidate YbZnGaO${}_4$

Abstract

Disorder is important in the study of quantum spin liquids, but its role on the spin dynamics remains elusive. Here, we explore the disorder effect by investigating the magnetic-field dependence of the low-energy magnetic excitations in a triangular-lattice frustrated magnet YbZnGaO${}_4$ with inelastic neutron scattering. With an intermediate field of 2.5 T applied along the $c$-axis, the broad continuum at zero field becomes more smeared both in energy and momentum. With a field up to 10 T, which fully polarizes the magnetic moments, we observe clear spin-wave excitations with a gap of $\sim$1.4 meV comparable to the bandwidth. However, the spectra are significantly broadened. The excitation spectra both at zero and high fields can be reproduced by performing classical Monte Carlo simulations which take into account the disorder effect arising from the random site mixing of nonmagnetic Zn${}^{2+}$ and Ga${}^{3+}$ ions. These results elucidate the critical role of disorder in broadening the magnetic excitation spectra and mimicking the spin-liquid features in frustrated quantum magnets.

arXiv commentPublished in PRB, 10 pages, 3 figures

References in corpus (62)

• Fault-tolerant quantum computation by anyons
• Anyons in an exactly solved model and beyond
• Mott Insulators in the Strong Spin-Orbit Coupling Limit: From Heisenberg to a Quantum Compass and Kitaev Models
• Quantum Spin Liquids
• Quantum Spin Liquid States
• Fractionalized excitations in the spin liquid state of a kagomé lattice antiferromagnet
• Spin Liquid State in an Organic Mott Insulator with Triangular Lattice
• Quantum Spin Liquids
• Spin Dynamics of the Spin-1/2 Kagome Lattice Antiferromagnet ZnCu_3(OH)_6Cl_2
• Kitaev quantum spin liquid - concept and materialization
• Models and Materials for Generalized Kitaev Magnetism
• Herbertsmithite and the Search for the Quantum Spin Liquid
• Continuous excitations of the triangular-lattice quantum spin liquid YbMgGaO4
• Rare-earth triangular lattice spin liquid: a single-crystal study of YbMgGaO${}_4$
• Evidence for a spinon Fermi surface in a triangular lattice quantum spin liquid candidate
• Gapless quantum spin liquid ground state in the two-dimensional spin-1/2 triangular antiferromagnet YbMgGaO${}_4$
• Mott Transition from a Spin Liquid to a Fermi Liquid in the Spin-Frustrated Organic Conductor kappa-(ET)2Cu2(CN)3
• Field-tunable quantum disordered ground state in the triangular lattice antiferromagnet NaYbO${}_2$
• Disorder-Induced Mimicry of a Spin Liquid in YbMgGaO${}_4$
• Experimental identification of quantum spin liquids
• Spin-wave excitations evidencing the Kitaev interaction in single crystalline $\alpha$-RuCl${}_3$
• $\mu$SR evidence for the U(1) quantum spin liquid ground state in the triangular antiferromagnet YbMgGaO${}_4$
• Valence Bonds in Random Quantum Magnets: Theory and Application to YbMgGaO4
• Rare-earth chalcogenides: A large family of triangular lattice spin liquid candidate
• Crystalline Electric Field Randomness in the Triangular Lattice Spin-Liquid YbMgGaO${}_4$
• NaYbS${}_2$ - a new planar spin-$\frac{1}{2}$ triangular-lattice magnet and putative spin liquid
• Gapless spin-liquid state in the structurally disorder-free triangular antiferromagnet NaYbO${}_2$
• Critical level crossings and gapless spin liquid in the square-lattice spin-$1/2$ $J_1$-$J_2$ Heisenberg antiferromagnet
• Spin-glass ground state in a triangular-lattice compound YbZnGaO${}_4$
• Physical realization of a quantum spin liquid based on a novel frustration mechanism
• Topography of Spin Liquids on a Triangular Lattice
• Gapped spin-1/2 spinon excitations in a new kagome quantum spin liquid compound Cu${}_3$Zn(OH)${}_6$FBr
• Absence of magnetic thermal conductivity in the quantum spin liquid candidate YbMgGaO4
• Scaling and data collapse from local moments in frustrated disordered quantum spin systems
• Anisotropic-Exchange Magnets on a Triangular Lattice: Spin Waves, Accidental Degeneracies, and Dual Spin Liquids
• Spin-liquid-like state in a spin-1/2 square-lattice antiferromagnet perovskite induced by $d^{10}$-$d^0$ cation mixing
• Quantum spin liquid ground state in the disorder free triangular lattice NaYbS${}_2$
• Vacancy defects and monopole dynamics in oxygen-deficient pyrochlores
• Gapless spin liquid and valence-bond solid in the $J_1-J_2$ Heisenberg model on the square lattice: insights from singlet and triplet excitations
• The Spinon Fermi Surface U(1) Spin Liquid in a Spin-Orbit-Coupled Triangular Lattice Mott Insulator YbMgGaO4
• Gapless spin liquid ground state of spin-1/2 $J_1$-$J_2$ Heisenberg model on square lattices
• Hierarchy of exchange interactions in the triangular-lattice spin-liquid YbMgGaO${}_4$
• Nearest-neighbor resonating valence bonds in YbMgGaO4
• Fractionalized excitations in the partially magnetized spin liquid candidate YbMgGaO4
• Ground-state phase diagram of an anisotropic spin-$1/2$ model on the triangular lattice
• Rearrangement of uncorrelated valence bonds evidenced by low-energy spin excitations in YbMgGaO4
• Survival of itinerant excitations and quantum spin state transitions in YbMgGaO${}_4$ with chemical disorder
• Spin wave spectrum of the quantum ferromagnet on the pyrochlore lattice Lu2V2O7
• The effect of spin-orbit coupling on the effective-spin correlation in YbMgGaO4
• Detecting spin fractionalization in a spinon Fermi surface spin liquid
• Coherent Transmutation of Electrons into Fractionalized Anyons
• Quasi-continuous transition from a Fermi liquid to a spin liquid
• Spectral properties of the square-lattice antiferromagnetic J1-J2 Heisenberg model: confinement and deconfinement of spinons
• Finite-temperature behavior of a classical spin-orbit-coupled model for ${\text{YbMgGaO}}_4$ with and without bond disorder
• Role of defects in determining the magnetic ground state of ytterbium titanate
• Disorder-induced spin-liquid-like behavior in kagome-lattice compounds
• Persistent spin dynamics and absence of spin freezing in the $H$-$T$ phase diagram of the 2D triangular antiferromagnet YbMgGaO${}_4$
• Exact diagonalization study of the anisotropic Heisenberg model related to YbMgGaO${}_4$
• Field evolution of the spin-liquid candidate YbMgGaO${}_4$
• Phase Diagram of YbZnGaO4 in Applied Magnetic Field
• Persistent spin dynamics in the pressurized spin-liquid candidate YbMgGaO${}_4$
• Reinvestigation of the homogeneous spin model in YbMgGaO${}_4$

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• Neutron spectroscopy evidence for a possible magnetic-field-induced gapless quantum-spin-liquid phase in a Kitaev material $\alpha$-RuCl${}_3$
• Signatures of a gapless quantum spin liquid in the Kitaev material Na${}_3$Co${}_{2-x}$Zn${}_x$SbO${}_6$
• Spin Excitation Continuum in the Exactly Solvable Triangular-Lattice Spin Liquid CeMgAl11O19
• Quantum selection of order and dynamic properties of Kitaev-Heisenberg ferromagnet on a triangular lattice
• Recent progress in quantum spin liquids, fractional magnetization plateaus, and unconventional superconductivity in kagome lattices
• Disorder-induced spin excitation continuum and spin-glass ground state in the inverse spinel CuGa${}_2$O${}_4$
• Interplay of disorder and spin liquid physics in the triangular-lattice antiferromagnet YbZn2GaO5