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arXiv · 0911.2648

The Transition from Heavy Fermion to Mixed Valence in Ce1-xYxAl3: A Quantitative Comparison with the Anderson Impurity Model

E. A. Goremychkin·R. Osborn·I. L. Sashin·P. Riseborough·B. D. Rainford·D. T. Adroja·J. M. Lawrence
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Abstract

We present a neutron scattering investigation of Ce1-xYxAl3 as a function of chemical pressure, which induces a transition from heavy-fermion behavior in CeAl3 (TK=5 K) to a mixed-valence state at x=0.5 (TK=150 K). The crossover can be modeled accurately on an absolute intensity scale by an increase in the k-f hybridization, Vkf, within the Anderson impurity model. Surprisingly, the principal effect of the increasing Vkf is not to broaden the low-energy components of the dynamic magnetic susceptibility but to transfer spectral weight to high energy.

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E. A. Goremychkin, R. Osborn, I. L. Sashin, P. Riseborough, B. D. Rainford, D. T. Adroja, J. M. Lawrence. 2010-06-02. The Transition from Heavy Fermion to Mixed Valence in Ce1-xYxAl3: A Quantitative Comparison with the Anderson Impurity Model. https://doi.org/10.1103/physrevlett.104.176402

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