Title: Magnetisation as a function of time and field.

Giblin SR (2016). Magnetisation as a function of time and field.. Cardiff University. http://doi.org/10.17035/d.2016.0008219696

Access Rights: Data can be made freely available subject to attribution
Access Method: Click to email a request for this data to opendata@cardiff.ac.uk

Cardiff University Dataset Creators

Dataset Details
Publisher: Cardiff University
Date (year) of data becoming publicly available: 2016
Data format: .xlxs
Estimated total storage size of dataset: Less than 100 megabytes
Number of Files In Dataset: 1
DOI: 10.17035/d.2016.0008219696


A non-Ohmic current that grows exponentially with the square root of applied electric field is well known from thermionic field emission (the Schottky effct), electrolytes (the second Wien effct) and semiconductors (the Poole-Frenkel effect). It is a universal signature of the attractive Coulomb force between positive and negative electrical charges, which is revealed as the charges are driven in opposite directions by the force of an applied electric field. Here we apply thermal quenches to spin ice to prepare metastable populations of bound pairs of positive and negative emergent magnetic monopoles at millikelvin temperatures. We find that the application of a magnetic field results in a universal exponential-root field growth of magnetic current, thus confirming the microscopic Coulomb force between the magnetic monopole quasiparticles and establishing a magnetic analogue of the Poole-Frenkel effect. At temperatures above 300 mK, gradual restoration of kinetic monopole equilibria causes the non-Ohmic current to smoothly evolve into the high field Wien effect for magnetic monopoles, as confirmed by comparison to a recent and rigorous theory of the Wien effect in spin ice. Our results extend the universality of the exponential-root field form into magnetism and illustrate the power of emergent particle kinetics to describe far-from equilibrium response in complex systems.

The data comprises magnetisation as a function of time (up to <= 1300s) for different field in spin ice for a range of magenetic field values 0.01 - 0.14T in 0.01T increments.

Research results based upon these data are available at http://doi.org/10.1038/nphys3704

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Last updated on 2019-05-07 at 13:32