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Disorder, inhomogeneity and spin dynamics in f-electron non-Fermi liquid systems

D. E. MacLaughlin·R. H. Heffner·O. O. Bernal·K. Ishida·J. E. Sonier·G. J. Nieuwenhuys·M. B. Maple·G R Stewart
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Abstract

Muon spin rotation and relaxation ($μ$SR) experiments have yielded evidence that structural disorder is an important factor in many f-electron-based non-Fermi-liquid (NFL) systems. Disorder-driven mechanisms for NFL behaviour are suggested by the observed broad and strongly temperature-dependent $μ$SR (and NMR) linewidths in several NFL compounds and alloys. Local disorder-driven theories (Kondo disorder, Griffiths-McCoy singularity) are, however, not capable of describing the time-field scaling seen in muon spin relaxation experiments, which suggest cooperative and critical spin fluctuations rather than a distribution of local fluctuation rates. A strong empirical correlation is established between electronic disorder and slow spin fluctuations in NFL materials

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D. E. MacLaughlin, R. H. Heffner, O. O. Bernal, K. Ishida, J. E. Sonier, G. J. Nieuwenhuys, M. B. Maple, G R Stewart. 2004-04-06. Disorder, inhomogeneity and spin dynamics in f-electron non-Fermi liquid systems. https://doi.org/10.1088/0953-8984%2F16%2F40%2F005

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