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arXiv · 1401.1881

From local moment to mixed-valence regime in Ce(1-x)Yb(x)CoIn5 alloys

Y. P. Singh·D. J. Haney·X. Y. Huang·I. K. Lum·B. D. White·M. Dzero·M. B. Maple·C. C. Almasan
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Abstract

We investigated the onset of the many-body coherence in the f-orbital single crystalline alloys Ce(1-x)Yb(x)CoIn5 through thermodynamic and magneto-transport measurements. Our study shows the evolution of the many-body electronic state as the Kondo lattice of Ce moments is transformed into an array of Ce impurities. Specifically, we observe a smooth crossover from the predominantly localized Ce moment regime to the predominantly itinerant Yb f-electronic states regime for about 50% of Yb doping. Our analysis of the residual resistivity data unveils the presence of correlations between Yb ions, while from our analysis of specific heat data we conclude that for 0.65<x<0.775, ytterbium f-electrons strongly interact with the conduction electrons while the Ce moments remain completely decoupled. The sub-linear temperature dependence of resistivity across the whole range of Yb concentrations suggest the presence of a nontrivial scattering mechanism for the conduction electrons.

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Y. P. Singh, D. J. Haney, X. Y. Huang, I. K. Lum, B. D. White, M. Dzero, M. B. Maple, C. C. Almasan. 2014-01-09. From local moment to mixed-valence regime in Ce(1-x)Yb(x)CoIn5 alloys. https://doi.org/10.1103/physrevb.89.115106

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