Large energy gaps in CaC6 from tunneling spectroscopy:: Possible evidence of strong-coupling superconductivity

被引：18

作者：

Kurter, Cihan ^{[1
,2
]}

Ozyuzer, Lutfi ^{[1
,3
]}

Mazur, Daniel ^{[1
,2
]}

Zasadzinski, John F. ^{[2
]}

Rosenmann, Daniel ^{[1
]}

机构：

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

[2] IIT, Div Phys, Chicago, IL 60616 USA

[3] Izmir Inst Technol, Dept Phys, Izmir, Turkey

来源：

PHYSICAL REVIEW B | 2007年 / 76卷 / 22期

关键词：

D O I：

10.1103/PhysRevB.76.220502

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Tunneling in CaC6 crystals reproducibly reveals superconducting gaps Delta of 2.3 +/- 0.2 meV that are similar to 40% larger than reported earlier. In an isotropic s-wave scenario, that puts CaC6 into the class of very strongly coupled superconductors, since 2 Delta/kT(c)similar to 4.6, implying that soft Ca phonons are primarily involved in the superconductivity. This conclusion explains the relatively large Ca isotope effect found recently for CaC6, but it could also signal a strong anisotropy in the electron-phonon interaction.

引用

页数：4

共 19 条

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