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Slow Spin Dynamics in Non-Fermi-Liquid UCu_{5-x}Pd_x, x = 1.0 and 1.5

D. E. MacLaughlin·R. H. Heffner·O. O. Bernal·G. J. Nieuwenhuys·J. E. Sonier·M. S. Rose·R. Chau·M. B. Maple·B. Andraka
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Abstract

Low-temperature muon spin-lattice relaxation measurements in the non-Fermi-liquid heavy-fermion alloys UCu_{5-x}Pd_x, x = 1.0 and 1.5, indicate inhomogeneously distributed f-electron spin fluctuation rates, and exhibit a time-field scaling of the muon relaxation function indicative of long-lived spin correlations. In UCu_4Pd the scaling exponent γis small and temperature independent. In UCu_{3.5}Pd_{1.5} γvaries with temperature, increasing with decreasing temperature similar to spin-glass AgMn. This suggests that the spin-glass state found for x \gtrsim 2 in UCu_{5-x}Pd_x modifies the low-frequency spin dynamics in UCu_{3.5}Pd_{1.5}.

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D. E. MacLaughlin, R. H. Heffner, O. O. Bernal, G. J. Nieuwenhuys, J. E. Sonier, M. S. Rose, R. Chau, M. B. Maple, B. Andraka. 2001-09-05. Slow Spin Dynamics in Non-Fermi-Liquid UCu_{5-x}Pd_x, x = 1.0 and 1.5. https://doi.org/10.1016/s0921-4526(01)01169-3

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