Spin dynamics of the ordered dipolar-octupolar pseudospin-${}^1{/}_2$ pyrochlore Nd${}_2$Zr${}_2$O${}_7$ probed by muon spin relaxation

Abstract

We present a muon spin relaxation study on the Ising pyrochlore Nd${}_2$Zr${}_2$O${}_7$ which develops an "all-in-all-out" magnetic order below 0.4~K. At 20~mK far below the ordering transition temperature, the zero-field muon spin relaxation spectra show no static features and can be well described by a dynamical Gaussian-broadened Gaussian Kubo-Toyabe function indicating strong fluctuations of the ordered state. The spectra of the paramagnetic state (below 4.2~K) reveal anomalously slow paramagnetic spin dynamics and show only small difference with the spectra of the ordered state. We find that the fluctuation rate decreases with decreasing temperature and becomes nearly temperature independent below the transition temperature indicating persistent slow spin dynamics in the ground state. The field distribution width shows a small but sudden increase at the transition temperature and then becomes almost constant. The spectra in applied longitudinal fields are well fitted by the conventional dynamical Gaussian Kubo-Toyabe function, which further supports the dynamical nature of the ground state. The fluctuation rate shows a peak as a function of external field which is associated with a field-induced spin-flip transition. The strong dynamics in the ordered state are attributed to the transverse coupling of the Ising spins introduced by the multipole interactions.

arXiv comment9 pages, 12 figures

References in corpus (25)

• Magnetic Monopoles in Spin Ice
• Magnetic Pyrochlore Oxides
• Spin-lattice coupling in frustrated antiferromagnets
• Pyrochlore Photons: The U(1) Spin Liquid in a S=1/2 Three-Dimensional Frustrated Magnet
• Dirac Strings and Magnetic Monopoles in Spin Ice Dy2Ti2O7
• Quantum Excitations in Quantum Spin Ice
• Coulombic Quantum Liquids in Spin-1/2 Pyrochlores
• Dynamically-Induced Frustration as a Route to a Quantum Spin Ice State in Tb2Ti2O7 via Virtual Crystal Field Excitations and Quantum Many-Body Effects
• Quantum spin ices and topological phases from dipolar-octupolar doublets on the pyrochlore lattice
• First Order Transition in the Spin Dynamics of Geometrically Frustrated Yb2Ti2O7
• Quantum fluctuations in the effective pseudospin-1/2 model for magnetic pyrochlore oxides
• Magnetic-Moment Fragmentation and Monopole Crystallization
• Quantum Melting of Spin Ice: Emergent Cooperative Quadrupole and Chirality
• Investigation of the magnetic structure and crystal field states of pyrochlore antiferromagnet Nd2Zr2O7
• Fluctuations and all-in$-$all-out ordering in dipole-octupole Nd2Zr2O7
• Spin dynamics and magnetic order in magnetically frustrated Tb2Sn2O7
• How quantum are classical spin ices?
• An anisotropic local modification of crystal field levels in Pr-based pyrochlores: a muon-induced effect modelled using density functional theory
• Observation of long range magnetic ordering in pyrohafnate Nd2Hf2O7: A neutron diffraction study
• Direct evidence for a dynamical ground state in the highly frustrated Tb${}_2$Sn${}_2$O${}_7$ pyrochlore
• Gapless quantum excitations from an Ice-like Splayed Ferromagnetic ground state in stoichiometric Yb2Ti2O7
• Nd2Sn2O7: an all-in-all-out pyrochlore magnet with no divergence-free field and anomalously slow paramagnetic spin dynamics
• Absence of magnetic order in Yb3Ga5O12: relation between phase transition and entropy in geometrically frustrated materials
• Evidence for unidimensional low-energy excitations as the origin of persistent spin dynamics in geometrically frustrated magnets
• Anomalously slow spin dynamics and short-range correlations in the quantum spin ice systems Yb2Ti2O7 and Yb2Sn2O7

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• Worm-algorithm-type Simulation of Quantum Transverse-Field Ising Model
• Quantum Spin Ice Response to a Magnetic Field in the Dipole-Octupole Pyrochlore Ce${}_2$Zr${}_2$O${}_7$
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• Physical properties of the trigonal binary compound Nd${}_2$O${}_3$
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• Deviation from the dipole-ice model in the new spinel spin-ice candidate, MgEr${}_2$Se${}_4$
• $\mu$SR Study of the Dipole-Octupole Quantum Spin Ice Candidate Ce${}_2$Zr${}_2$O${}_7$
• Slow spin tunneling in the paramagnetic phase of the pyrochlore Nd2Sn2O7
• Pinch points and half-moons in dipolar-octupolar Nd${}_2$Hf${}_2$O${}_7$