Direct evidence for two-band superconductivity in MgB2 single crystals from directional point-contact spectroscopy in magnetic fields -: art. no. 247004

被引：235

作者：

Gonnelli, RS

Daghero, D

Ummarino, GA

Stepanov, VA

Jun, J

Kazakov, SM

Karpinski, J

机构：

[1] Politecn Torino, Dipartimento Fis, INFM, I-10129 Turin, Italy

[2] Russian Acad Sci, PN Lebedev Phys Inst, Moscow 119991, Russia

[3] Swiss Fed Inst Technol, Swiss Fed Inst Technol, Solid State Phys Lab, CH-8093 Zurich, Switzerland

来源：

PHYSICAL REVIEW LETTERS | 2002年 / 89卷 / 24期

关键词：

D O I：

10.1103/PhysRevLett.89.247004

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

We present the results of the first directional point-contact spectroscopy experiments in high-quality MgB2 single crystals. Because of the directionality of the current injection into the samples, the application of a magnetic field allowed us to separate the contributions of the sigma and pi bands to the total conductance of our point contacts. By using this technique, we were able to obtain the temperature dependency of each gap independent of the other. The consequent, strong reduction of the error on the value of the gap amplitude as a function of temperature allows a stricter test of the predictions of the two-band model for MgB2.

引用

页数：4

共 21 条

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An, J.M., 2001, American Institute of Physics Inc. (86)

[2] Temperature and field dependence of the anisotropy of MgB2 -: art. no. 167004 [J].