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Thickness dependence of the ground-state properties in thin films of the heavy-fermion compound CeCu_6

D. Groten·G. J. C. van Baarle·J. Aarts·G. J. Nieuwenhuys·J. A. Mydosh
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Abstract

High-quality thin polycrystalline films of the heavy-fermion compound CeCu_6 were prepared by sputter deposition. The thicker of these films (with thickness up to around 200 nm) reproduce the properties of the bulk compound CeCu_6. As the thickness of the films is decreased, our measurements display strong deviations from the bulk properties, namely, a suppression of the heavy-fermion state. We show that possible `external' effects, like disorder, oxidation and morphology can be excluded and that this size effect is therefore an intrinsic property of CeCu_6. In addition, we investigate possible scenarios explaining the size effect, and find that the proximity of CeCu_6 to a quantum phase transition can account for this striking result.

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D. Groten, G. J. C. van Baarle, J. Aarts, G. J. Nieuwenhuys, J. A. Mydosh. 2001-07-03. Thickness dependence of the ground-state properties in thin films of the heavy-fermion compound CeCu_6. https://arxiv.org/abs/cond-mat/0107049

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