Spin Ice: Magnetic Excitations without Monopole Signatures using Muon Spin Rotation

Abstract

Theory predicts the low-temperature magnetic excitations in spin ices consist of deconfined magnetic charges, or monopoles. A recent transverse-field (TF) muon spin rotation (muSR) experiment [S T Bramwell et al, Nature 461, 956 (2009)] reports results claiming to be consistent with the temperature and magnetic field dependence anticipated for monopole nucleation - the so-called second Wien effect. We demonstrate via a new series of muSR experiments in Dy_2Ti_2O_7 that such an effect is not observable in a TF muSR experiment. Rather, as found in many highly frustrated magnetic materials, we observe spin fluctuations which become temperature independent at low temperatures, behavior which dominates over any possible signature of thermally nucleated monopole excitations.

6 pages; 4 figures; published in Phys Rev. Lett. 107, 207207 (2011); Supplementary material and body of paper combined together in 1 file

References in corpus (7)

• Dynamically-Induced Frustration as a Route to a Quantum Spin Ice State in Tb2Ti2O7 via Virtual Crystal Field Excitations and Quantum Many-Body Effects
• Low Temperature Spin Freezing in Dy2Ti2O7 Spin Ice
• Why spin ice obeys the ice rules
• Dy2Ti2O7 Spin Ice: a Test Case for Emergent Clusters in a Frustrated Magnet
• Brownian Motion and Quantum Dynamics of Magnetic Monopoles in Spin Ice
• High-temperature spin relaxation process in Dy${}_2$Ti${}_2$O${}_7$ probed by ${}^{47}$Ti-NQR
• Calculation of the Expected Zero Field Muon Relaxation Rate in the Geometrically Frustrated Rare Earth Pyrochlore Gd2Sn2O7 Antiferromagnet

Cited by in corpus (38)

• Quantum Spin Ice: A Search for Gapless Quantum Spin Liquids in Pyrochlore Magnets
• Magnetic-Moment Fragmentation and Monopole Crystallization
• Magnetic Order in the Pyrochlore Iridates A2Ir2O7 (A = Y, Yb)
• Onsager's Wien Effect on a Lattice
• Brownian Motion and Quantum Dynamics of Magnetic Monopoles in Spin Ice
• Direct Evidence for the 'All-in/All-out' Magnetic Structure in the Pyrochlore Iridates from $\mu$SR
• Unconventional Magnetic Ground State in Yb${}_2$Ti${}_2$O${}_7$
• Coulomb spin liquid in anion-disordered pyrochlore Tb${}_2$Hf${}_2$O${}_7$
• Single-ion anisotropy and magnetic field response in spin ice materials Ho${}_2$Ti${}_2$O${}_7$ and Dy${}_2$Ti${}_2$O${}_7$
• New physics in frustrated magnets: Spin ices, monopoles, etc
• The Spectral Periodicity of Spinon Continuum in Quantum Spin Ice
• A Supercooled Spin Liquid State in the Frustrated Pyrochlore Dy2Ti2O7
• Dirac's "magnetic monopole" in pyrochlore ice U(1) spin liquids: Spectrum and classification
• Fragmentation in Frustrated Magnets -- A review
• Monopoles, magnetricity and the stray field from spin ice
• Pyrochlore U(1) spin liquid of mixed symmetry enrichments in magnetic fields
• Experimental signature of the attractive Coulomb force between positive and negative magnetic monopoles in spin ice
• Correlated Quantum Tunnelling of Monopoles in Spin Ice
• Toward the computational prediction of muon sites and interaction parameters
• Thermal Conductivity and Specific Heat of the Spin-Ice Compound Dy${}_2$Ti${}_2$O${}_7$: Experimental Evidence for Monopole Heat Transport
• Evidence for unidimensional low-energy excitations as the origin of persistent spin dynamics in geometrically frustrated magnets
• Competing phases and topological excitations of spin-one pyrochlore antiferromagnets
• AC Wien effect in spin ice, manifest in non-linear non-equilibrium susceptibility
• Melting of Spin Ice state through structural disorder in Dy2Zr2O7
• A field trip through spin ice
• Generalised Longitudinal Susceptibility for Magnetic Monopoles in Spin Ice
• An irreversible magnetic-field dependence of low-temperature heat transport of spin-ice compound Dy_2Ti_2O_7 in a [111] field
• Coulombic Charge Ice
• Possible Quantum Diffusion of Polaronic Muons in Dy${}_2$Ti${}_2$O${}_7$ Spin Ice
• Low-temperature muon spin rotation studies of the monopole charges and currents in Y doped Ho2Ti2O7
• Dichotomous Dynamics of Magnetic Monopole Fluids
• Muon diffusion and electronic magnetism in Y${}_2$Ti${}_2$O${}_7$
• Possible spin frustration in Nd${}_2$Ti${}_2$O${}_7$ probed by muon spin relaxation
• Spin structure factor and thermodynamics in the antiferromagnetic quantum Ising model in the pyrochlore lattice
• Magnetic charge's relaxation propelled electricity in two-dimensional magnetic honeycomb lattice
• Three-dimensional Sandglass Magnet with Non-Kramers ions
• Photon Polarization Precession Spectroscopy for High-Resolution Studies of Spinwaves
• Low frequency spin dynamics in XY quantum spin ice Yb${}_2$Pt${}_2$O${}_7$