Nonadiabatic channels in the superconducting pairing of fullerides

被引:37
作者
Cappelluti, E
Grimaldi, C
Pietronero, L
Strässler, S
机构
[1] Univ Rome La Sapienza, Dipartimento Fis, I-00185 Rome, Italy
[2] INFM, Unita Roma 1, Rome, Italy
[3] Ecole Polytech Fed Lausanne, IPM, Dept Microtech, CH-1015 Lausanne, Switzerland
关键词
D O I
10.1103/PhysRevLett.85.4771
中图分类号
O4 [物理学];
学科分类号
0702 ;
摘要
We show the intrinsic inconsistency of the conventional phonon mediated theory of superconductivity in relation to the observed properties of Rb3C60 The recent, highly accurate measurement of the carbon isotope coefficient alpha (C) = 0.21, together with the high value of T-c (30 K) and the very small Fermi energy E-F (0.25 eV), unavoidably implies the opening of nonadiabatic channels in the superconducting pairing. We estimate these effects and show that they are actually the key elements for the high value of T-c in these materials compared to the very low values of graphite intercalation compounds.
引用
收藏
页码:4771 / 4774
页数:4
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