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arXiv · cond-mat/9809243

Muon Spin Relaxation and Nonmagnetic Kondo State in PrInAg_2

Abstract

Muon spin relaxation experiments have been carried out in the Kondo compound PrInAg_2. The zero-field muon relaxation rate is found to be independent of temperature between 0.1 and 10 K, which rules out a magnetic origin (spin freezing or a conventional Kondo effect) for the previously-observed specific heat anomaly at \sim0.5 K. The low-temperature muon relaxation is quantitatively consistent with nuclear magnetism including hyperfine enhancement of the ^{141}Pr nuclear moment. This is strong evidence against a Pr^{3+} electronic magnetic moment, and for the Γ_3 crystalline-electric-field-split ground state required for a nonmagnetic route to heavy-electron behavior. The data imply the existence of an exchange interaction between neighboring Pr^{3+} ions of the order of 0.2 K in temperature units, which should be taken into account in a complete theory of a nonmagnetic Kondo effect in PrInAg_2.

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BibTeXRIS

D. E. MacLaughlin, R. H. Heffner, G. J. Nieuwenhuys, P. C. Canfield, A. Amato, C. Baines, A. Schenck, G. M. Luke, Y. Fudamoto, Y. J. Uemura. 1998-09-17. Muon Spin Relaxation and Nonmagnetic Kondo State in PrInAg_2. https://arxiv.org/abs/cond-mat/9809243

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