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arXiv · 1810.04847

Observation of magnetic structural universality using transverse NMR relaxation

Alexander Ruh·Philipp Emerich·Harald Scherer·Dmitry S. Novikov·Valerij G. Kiselev
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Abstract

Transverse NMR relaxation from spins diffusing through a random magnetic medium is sensitive to its structure on a mesoscopic scale. In particular, this results in the time-dependent relaxation rate. We show analytically and numerically that this rate approaches the long-time limit in a power-law fashion, with the exponent reflecting the disorder class of mesoscopic magnetic structure. The spectral line shape acquires a corresponding non-analytic power law singularity at zero frequency. We experimentally detect a change in the dynamical exponent as a result of the transition into a maximally random jammed state characterized by hyperuniform correlations.

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Alexander Ruh, Philipp Emerich, Harald Scherer, Dmitry S. Novikov, Valerij G. Kiselev. 2018-10-11. Observation of magnetic structural universality using transverse NMR relaxation. https://arxiv.org/abs/1810.04847

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