Thickness dependence of the ground-state properties of thin films of the heavy-fermion compound CeCu 6
Thickness dependence of the ground-state properties of thin films of the heavy-fermion compound CeCu 6
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重费米子化合物CeCu 6 薄膜基态特性的厚度依赖性
DOI：
10.1103/physrevb.64.144425
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发表时间：
2001
期刊：
影响因子：
--
通讯作者：
J. Mydosh
中科院分区：
文献类型：
--
作者：
D. Groten;G. V. Baarle;J. Aarts;G. Nieuwenhuys;J. Mydosh
采用溅射沉积法制备了高质量的重费米子化合物CeCu6多晶薄膜。较厚的薄膜(厚度可达200 nm左右)重现了块体化合物CeCu6的性质。随着薄膜厚度的减小，我们的测量结果与块体性质有很大的偏差，即重费米子态的抑制。我们发现，可以排除可能的“外部”效应，如无序、氧化和形态，因此这种尺寸效应是CeCu6的固有特性。此外，我们研究了解释尺寸效应的可能场景，并发现CeCu6接近量子相变可以解释这一惊人的结果。
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.