Low-energy Spin Dynamics of Quantum Spin Liquid Candidate $NaYbS{e}_2$

Abstract

The family of rare earth chalcogenides $AREC{h}_2$ (A = alkali or monovalent ions, RE = rare earth, and Ch = O, S, Se, and Te) appears as an inspiring playground for studying quantum spin liquids (QSL). The crucial low-energy spin dynamics remain to be uncovered. By employing muon spin relaxation ($\mu$SR) and zero-field (ZF) AC susceptibility down to 50 mK, we are able to identify the gapless QSL in $NaYbS{e}_2$, a representative member with an effective spin-1/2, and explore its unusual spin dynamics. The ZF $\mu$SR experiments unambiguously rule out spin ordering or freezing in $NaYbS{e}_2$ down to 50 mK, two orders of magnitude smaller than the exchange coupling energies. The spin relaxation rate, $\lambda$, approaches a constant below 0.3 K, indicating finite spin excitations featured by a gapless QSL ground state. This is consistently supported by our AC susceptibility measurements. The careful analysis of the longitudinal field (LF) $\mu$SR spectra reveals a strong spatial correlation and a temporal correlation in the spin-disordered ground state, highlighting the unique feature of spin entanglement in the QSL state. The observations allow us to establish an experimental H-T phase diagram. The study offers insight into the rich and exotic magnetism of the rare earth family.

21 pages, 18 figures

References in corpus (7)

• Mantid - Data Analysis and Visualization Package for Neutron Scattering and $\mu SR$ Experiments
• $\mu$SR evidence for the U(1) quantum spin liquid ground state in the triangular antiferromagnet YbMgGaO${}_4$
• Anisotropic field-induced ordering in the triangular-lattice quantum spin liquid NaYbSe${}_2$
• Interplay of Rare Earth and Iron magnetism in RFeAsO with R = La, Ce, Pr, and Sm: A muon spin relaxation study and symmetry analysis
• Quantum spin liquid ground state in the disorder free triangular lattice NaYbS${}_2$
• Field-induced magnetic transition and spin fluctuation in quantum spin liquid candidate CsYbSe${}_2$
• Spin excitations in the frustrated triangular lattice antiferromagnet NaYbO${}_2$

Cited by in corpus (15)

• Evidence of Dirac Quantum Spin Liquid in YbZn2GaO5
• Non-linear magnons and exchange Hamiltonians of delafossite proximate quantum spin liquids
• Rare-Earth Chalcogenides: An Inspiring Playground For Exploring Frustrated Magnetism
• Evidence of quantum spin liquid state in a Cu${}^{2+}$-based $S=1/2$ triangular lattice antiferromagnet
• Magnetism of $\mathrm{NaYb}{\mathrm{S}}_2$: From finite temperatures to ground state
• Thermodynamics and heat transport of quantum spin liquid candidates NaYbS${}_2$ and NaYbSe${}_2$
• Frustration-induced quantum criticality in Ni-doped CePdAl as revealed by the $\mu$SR technique
• Structural and magnetic characterization of CeTa${}_7$O${}_{19}$ and YbTa${}_7$O${}_{19}$ with two-dimensional pseudospin-1/2 triangular lattice
• Anisotropic magnetism and spin fluctuations in the triangular-lattice spin-liquid candidate NaYbSe${}_2$: a single-crystal ${}^{23}$Na and ${}^{77}$Se NMR study
• Dominant Kitaev interaction and field-induced quantum phase transitions in triangular-lattice KCeSe2
• Gapless spinon excitations emerging from a multipolar transverse field in the triangular-lattice Ising antiferromagnet NaTmSe2
• Magnetic dilution in the triangular lattice antiferromagnet NaYb${}_{1-x}$Lu${}_x$O${}_2$
• Sign-problem-free effective models of triangular lattice quantum antiferromagnets
• Emergent Dispersive Multipolar Excitations in NaErSe${}_2$
• Finite Spinon Density-of-States in Triangular-Lattice Delafossite TlYbSe${}_2$