Specific heat measurement of the layered nitride superconductor LixZrNCl -: art. no. 217002

被引:69
作者
Taguchi, Y [1 ]
Hisakabe, M
Iwasa, Y
机构
[1] Tohoku Univ, Inst Mat Res, Sendai, Miyagi 9808577, Japan
[2] Japan Sci & Technol Corp, CREST, Kawaguchi 3320012, Japan
关键词
D O I
10.1103/PhysRevLett.94.217002
中图分类号
O4 [物理学];
学科分类号
0702 ;
摘要
Specific heat has been investigated in a layered nitride superconductor, Li0.12ZrNCl, with T-c=12.7 K. The obtained data have shown a marked dichotomy: The specific heat jump at T-c (Delta C/gamma T-n(c)=1.8) and the superconducting gap ratio (2 Delta/k(B)T(c)=4.6-5.2) have indicated an intermediate to a strong coupling of electrons, while the upper limit of the electron-phonon coupling constant lambda has directly been estimated to be 0.22, which belongs to a weak coupling regime. Furthermore, the rapid increase of gamma as a function of magnetic field suggests that the present material has an anisotropic s wave gap.
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页数:4
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