Emergent Electrochemistry in Spin Ice: Debye-Hückel Theory and Beyond

Abstract

The low-temperature picture of dipolar spin ice in terms of the Coulomb fluid of its fractionalised magnetic monopole excitations has allowed analytic and conceptual progress far beyond its original microscopic spin description. Here we develop its thermodynamic treatment as a `magnetolyte', a fluid of singly and doubly charged monopoles, an analogue of the electrochemical system $2{\mathrm{H}}_2\mathrm{O}={\mathrm{H}}_3{\mathrm{O}}^{+}+\mathrm{O}{\mathrm{H}}^{-}={\mathrm{H}}_4{\mathrm{O}}^{2+}+{\mathrm{O}}^{2-}$, but with perfect symmetry between oppositely charged ions. For this lattice magnetolyte, we present an analysis based on Debye-Hückel theory, which is accurate at all temperatures and incorporates `Dirac strings' imposed by the microscopic ice rule constraints at the level of Pauling's approximation. Our results are in close agreement with the specific heat from numerical simulations as well as new experimental measurements with an improved lattice correction, which we present here, on the spin ice materials $\mathrm{H}{\mathrm{o}}_2\mathrm{T}{\mathrm{i}}_2{\mathrm{O}}_7$ and $\mathrm{D}{\mathrm{y}}_2\mathrm{T}{\mathrm{i}}_2{\mathrm{O}}_7$. Our study of the magnetolyte shows how electrochemistry can emerge in non-electrical systems. We also provide new experimental tests of Debye-Hückel theory and its extensions. The application of our results also yields insights into the electrochemical behaviour of water ice and liquid water, which are closely related to the spin ice magnetolyte.

arXiv comment(15 pages, 6 figures)

References in corpus (40)

• Spin Ice State in Frustrated Magnetic Pyrochlore Materials
• Magnetic Monopoles in Spin Ice
• Electrostatic correlations: from Plasma to Biology
• Dipolar Interactions and Origin of Spin Ice in Ising Pyrochlore Magnets
• The "Coulomb phase" in frustrated systems
• Signature of magnetic monopole and Dirac string dynamics in spin ice
• Spin Correlations in Ho${}_2$Ti${}_2$O${}_7$: a Dipolar Spin Ice System
• Coulombic Quantum Liquids in Spin-1/2 Pyrochlores
• Long Range Order at Low Temperature in Dipolar Spin Ice
• Artificial square ice and related dipolar nanoarrays
• Thermodynamic Properties of the Dipolar Spin Ice Model
• Underscreening in concentrated electrolytes
• Magnetic-Moment Fragmentation and Monopole Crystallization
• Nanoscale capillary freezing of ionic liquids confined between metallic interfaces and the role of electronic screening
• Local Simulation Algorithms for Coulomb Interaction
• Specific Heat of Kagome Ice in the Pyrochlore Oxide Dy2Ti2O7
• Dy2Ti2O7 Spin Ice: a Test Case for Emergent Clusters in a Frustrated Magnet
• Magnetic Monopole Dynamics in Spin Ice
• Magnetization process of spin ice in a [111] magnetic field
• The origin of the Debye relaxation in liquid water and fitting the high frequency excess response
• Static and Dynamic Critical Behavior of a Symmetrical Binary Fluid: A Computer Simulation
• Debye-Hückel theory for spin ice at low temperature
• Onsager's Wien Effect on a Lattice
• Ice: a strongly correlated proton system
• Fractional charges in pyrochlore lattices
• Lattice Models of Ionic Systems
• Analysis of a fully packed loop model arising in a magnetic Coulomb phase
• Topological Sector Fluctuations and Curie Law Crossover in Spin Ice
• Pauling entropy, metastability and equilibrium in Dy${}_2$Ti${}_2$O${}_7$ spin ice
• A Supercooled Spin Liquid State in the Frustrated Pyrochlore Dy2Ti2O7
• Charge ordering in a pure spin model: dipolar spin-ice
• First principles calculation and experimental investigation of lattice dynamics in the rare earth pyrochlores R2Ti2O7 (R=Tb, Dy, Ho)
• Experimental signature of the attractive Coulomb force between positive and negative magnetic monopoles in spin ice
• Coulomb phase diagnostics as function of temperature, interaction range and disorder
• Spin Ice Thin Film: Surface Ordering, Partial Magnetic Wetting and Emergent Square Ice
• AC Wien effect in spin ice, manifest in non-linear non-equilibrium susceptibility
• Monopole ordered phases in dipolar and nearest-neighbours Ising pyrochlore: from spin ice to the "all-in--all-out" antiferromagnet
• Spin ice thin films: Large-N theory and Monte Carlo simulations
• Topological-sector fluctuations and ergodicity breaking at the Berezinskii-Kosterlitz-Thouless transition
• Phase Diagram of the Lattice Restricted Primitive Model

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• Nuclear spin assisted quantum tunnelling of magnetic monopoles in spin ice
• Superconducting phase transition reveals an electromagnetic coupling to a scalar field potential that generates mechanical work
• Violation of the fluctuation-dissipation theorem and effective temperatures in spin ice
• Equilibrium Field Theory of Magnetic Monopoles in Degenerate Square Spin Ice: Correlations, Entropic Interactions, and Charge Screening Regimes
• The Concept of Spin Ice Graphs and a Field Theory for their Topological Monopoles and Charges
• Screening and the Pinch Point Paradox in Spin Ice
• Spin ice in a general applied magnetic field: Kasteleyn transition, magnetic torque and rotational magnetocaloric effect
• Experimental Measures of Topological Sector Fluctuations in the F-Model
• Neutron scattering from fragmented frustrated magnets
• Thermal Conductivity of Square Ice
• Power spectrum of magnetic relaxation in spin ice: anomalous diffusion in a Coulomb fluid
• A condensed-matter analogue of the false vacuum