Large Ca isotope effect in the CaC6 superconductor

被引：43

作者：

Hinks, D. G. ^{[1
]}

Rosenmann, D. ^{[1
]}

Claus, H. ^{[1
]}

Bailey, M. S. ^{[1
]}

Jorgensen, J. D. ^{[1
]}

机构：

[1] Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA

来源：

PHYSICAL REVIEW B | 2007年 / 75卷 / 01期

关键词：

D O I：

10.1103/PhysRevB.75.014509

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

We have measured the Ca isotope effect coefficient, alpha(Ca), in the newly discovered superconductor CaC6 and find a value of 0.53(2). This result shows that the superconductivity is dominated by coupling of the electrons by Ca phonon modes. The C phonons contribute very little, assuming that this material is a conventional electron-phonon coupled superconductor. Thus, in contrast to another layered material MgB2, where high-energy phonons in the B layers are responsible for the superconductivity, in layered CaC6 the phonons responsible for superconductivity are primarily low-energy modes of the intercalated Ca.

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页数：6

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