Superconducting and normal-state gaps in κ-(BEDT-TTF)2Cu(NCS)2 studied by STM spectroscopy

被引：24

作者：

Arai, T ^{[1
]}

Ichimura, K

Nomura, K

Takasaki, S

Yamada, J

Nakatsuji, S

Anzai, H

机构：

[1] Hokkaido Univ, Div Phys, Sapporo, Hokkaido 0600810, Japan

[2] Himeji Inst Technol, Dept Mat Sci, Kamigori, Hyogo 6781297, Japan

来源：

SOLID STATE COMMUNICATIONS | 2000年 / 116卷 / 12期

基金：

日本学术振兴会;

关键词：

organic crystals; superconductors; tunneling;

D O I：

10.1016/S0038-1098(00)00395-1

中图分类号：

O469 [凝聚态物理学];

学科分类号：

070205 ;

摘要：

Scanning tunneling microscope (STM) spectroscopy on the b-c plane of single crystals of an organic superconductor kappa-(BEDT-TTF)(2)Cu(NCS)(2) has been performed in superconducting and normal states with varying temperature. The temperature dependence of the zero-bias conductance dI/dV\(V=0) is well explained by the d-wave gap model considering the T-2 dependence of the broadening parameter of the one-electron level Gamma (T), which is obtained from the fitting of the dI/dV-V curves to the d-wave Sap model. The dI/dV-V curve shows a broad dip around the Fermi energy above T-c = 10.4 K. This pseudogap structure remains up to about 45 K. The magnitude of the pseudogap is much larger than that of the superconducting gap Delta (p) similar to 3 meV. (C) 2000 Elsevier Science Ltd. All rights reserved.

引用

页码：679 / 682

页数：4

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