Persistent spin dynamics and absence of spin freezing in the $H$-$T$ phase diagram of the 2D triangular antiferromagnet YbMgGaO${}_4$

Abstract

We report results of muon spin relaxation and rotation ($\mu$SR) experiments on the spin-liquid candidate~YbMgGaO${}_4$. No static magnetism $\gtrsim 0.003{\mu }_B$ per Yb ion, ordered or disordered, is observed down to 22~mK, a factor of two lower in temperature than previous measurements. Persistent (temperature-independent) spin dynamics are observed up to 0.20~K and at least 1~kOe, thus extending previous zero-field $\mu$SR results over a substantial region of the $H$-$T$ phase diagram. Knight shift measurements in a 10-kOe transverse field reveal two lines with nearly equal amplitudes. Inhomogeneous muon depolarization in a longitudinal field, previously characterized by stretched-exponential relaxation due to spatial inhomogeneity, is fit equally well with two exponentials, also of equal amplitudes. We attribute these results to two interstitial muon sites in the unit cell, rather than disorder or other spatial distribution. Further evidence for this attribution is found from agreement between the ratio of the two measured relaxation rates and calculated mean-square local Yb${}^{3+}$ dipolar fields at candidate muon sites. Zero-field data can be understood as a combination of two-exponential dynamic relaxation and quasistatic nuclear dipolar fields.

References in corpus (30)

• Quantum Spin Liquids
• Quantum Spin Liquid States
• Spin Liquid State in an Organic Mott Insulator with Triangular Lattice
• Spin Dynamics of the Spin-1/2 Kagome Lattice Antiferromagnet ZnCu_3(OH)_6Cl_2
• Spin-Liquid State in the S = 1/2 Hyperkagome Antiferromagnet Na4Ir3O8
• musrfit: A free platform-independent framework for muSR data analysis
• Stretched Exponential Relaxation Arising from a Continuous Sum of Exponential Decays
• Spin-polarized muons in condensed matter physics
• 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${}_4$
• Disorder-Induced Mimicry of a Spin Liquid in YbMgGaO${}_4$
• $\mu$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
• Crystalline Electric Field Randomness in the Triangular Lattice Spin-Liquid YbMgGaO${}_4$
• An anisotropic spin model of strong spin-orbit-coupled triangular antiferromagnets
• Spin-glass ground state in a triangular-lattice compound YbZnGaO${}_4$
• Absence of magnetic thermal conductivity in the quantum spin liquid candidate YbMgGaO4
• Gapless spin liquid ground state in the S=1/2 vanadium oxyfluoride kagome antiferromagnet [NH4]2[C7H14N][V7O6F18]
• Spin Liquid State in the 3D Frustrated Antiferromagnet PbCuTe2O6: NMR and muSR Studies
• The Spinon Fermi Surface U(1) Spin Liquid in a Spin-Orbit-Coupled Triangular Lattice Mott Insulator YbMgGaO4
• 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
• Detecting spin fractionalization in a spinon Fermi surface spin liquid
• Finite-temperature behavior of a classical spin-orbit-coupled model for ${\text{YbMgGaO}}_4$ with and without bond disorder
• Toward the computational prediction of muon sites and interaction parameters

Cited by in corpus (9)

• Spectral function of the $J_1-J_2$ Heisenberg model on the triangular lattice
• Disorder-induced broadening of the spin waves in a triangular-lattice quantum-spin-liquid candidate YbZnGaO${}_4$
• Exact diagonalization study of the anisotropic Heisenberg model related to YbMgGaO${}_4$
• Field evolution of the spin-liquid candidate YbMgGaO${}_4$
• Excitation Spectrum and Spin Hamiltonian of the Frustrated Quantum Ising Magnet Pr${}_3$BWO${}_9$
• Role of alkaline metal in the rare-earth triangular antiferromagnet KYbO${}_2$
• Constraining the Parameter Space of a Quantum Spin Liquid Candidate in Applied Field with Iterative Optimization
• Antiferromagnetism and Ising Ground States in the Rare-earth Garnet Nd${}_3$Ga${}_5$O${}_{12}$
• Anisotropic magnetism and spin fluctuations in the triangular-lattice spin-liquid candidate NaYbSe${}_2$: a single-crystal ${}^{23}$Na and ${}^{77}$Se NMR study