NMR relaxation in spin ice due to diffusing emergent monopoles

2012/10/30 by Christopher L. Henley, Henley, Christopher L.
Physics and Astronomy · #Advanced Condensed Matter Physics #FOS: Physical sciences #Physics of Superconductivity and Magnetism #Strongly Correlated Electrons (cond-mat.str-el) #Topological Materials and Phenomena #cond-mat.str-el

paper · pdf · doi:10.48550/arxiv.1210.8137

5 pages

arxiv created 2012/10/30 · openalex publication_date 2012/10/30 · arxiv updated 2012/10/31 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

At low temperatures, spin dynamics in ideal spin ice is due mainly to dilute, thermally excited magnetic monopole excitations. I consider how these will affect the dynamics of a nuclear spin (the same theory applies to muon spin resonance if implanted muons do not diffuse). Up to the time scale for nearby monopoles to be rearranged, a stretched-exponential form of the relaxation functions is expected. I work out the expected exponent in that exponential and the formulas for the T₁ (longitudinal) and T₂ (dephasing) relaxations, as a function of the monopole density. Experimental NMR is incompatible with the predictions and I suggest is due to magnetic impurities.

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