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Spin dynamics in a structurally ordered non-Fermi liquid compound: YbRh_2Si_2

K. Ishida·D. E. MacLaughlin·O. O. Bernal·R. H. Heffner·G. J. Nieuwenhuys·O. Trovarelli·C. Geibel·F. Steglich
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Abstract

Muon spin relaxation (muSR) experiments have been carried out at low temperatures in the non-Fermi-liquid heavy-fermion compound YbRh_2Si_2. The longitudinal-field muSR relaxation function is exponential, indicative that the dynamic spin fluctuations are homogeneous. The relaxation rate 1/T_1 varies with applied field as H^{-y}, y = 1.0 \pm 0.1, which implies a scaling law of the form χ''(ω) \propto ω^{-y} f(ω/T), \lim_{x\to0} f(x) = x for the dynamic spin susceptibility.

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K. Ishida, D. E. MacLaughlin, O. O. Bernal, R. H. Heffner, G. J. Nieuwenhuys, O. Trovarelli, C. Geibel, F. Steglich. 2002-07-18. Spin dynamics in a structurally ordered non-Fermi liquid compound: YbRh_2Si_2. https://doi.org/10.1016/s0921-4526(02)01646-0

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