Anisotropic Electron-Phonon Coupling and Dynamical Nesting on the Graphene Sheets in Superconducting CaC6 using Angle-Resolved Photoemission Spectroscopy

被引：79

作者：

Valla, T. ^{[1
]}

Camacho, J. ^{[1
]}

Pan, Z.-H. ^{[2
]}

Fedorov, A. V. ^{[2
]}

Walters, A. C. ^{[3
,4
]}

Howard, C. A. ^{[3
,4
]}

Ellerby, M. ^{[3
,4
]}

机构：

[1] Brookhaven Natl Lab, Condensed Matter Phys & Mat Sci Dept, Upton, NY 11973 USA

[2] Lawrence Berkeley Natl Lab, Adv Light Source, Berkeley, CA 94720 USA

[3] UCL, London Ctr Nanotechnol, London WC1E 6BT, England

[4] UCL, Dept Phys & Astron, London WC1E 6BT, England

来源：

PHYSICAL REVIEW LETTERS | 2009年 / 102卷 / 10期

基金：

英国工程与自然科学研究理事会;

关键词：

GRAPHITE; INTERCALATION; ENERGY; STATE;

D O I：

10.1103/PhysRevLett.102.107007

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

We present the first angle-resolved photoemission studies of electronic structure in CaC6, a superconducting graphite intercalation compound with T-c=11.6 K. We find that, contrary to theoretical models, the electron-phonon coupling on the graphene-derived Fermi sheets with high-frequency graphene-derived phonons is surprisingly strong and anisotropic. The shape of the Fermi surface is found to favor a dynamical intervalley nesting via exchange of high-frequency phonons. Our results suggest that graphene sheets play a crucial role in superconductivity in graphite intercalation compounds.

引用

页数：4

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