Evidence for two-band superconductivity from break-junction tunneling on MgB2 -: art. no. 127002

被引：145

作者：

Schmidt, H

Zasadzinski, JF

Gray, KE

Hinks, DG

机构：

[1] Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA

[2] IIT, Dept Phys, Chicago, IL 60616 USA

来源：

PHYSICAL REVIEW LETTERS | 2002年 / 88卷 / 12期

关键词：

D O I：

10.1103/PhysRevLett.88.127002

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

Superconductor-insulator-superconductor tunnel junctions have been fabricated on MgB2 that display Josephson and quasiparticle currents. These junctions exhibit a gap magnitude, Delta similar to 2.5 meV, that is considerably smaller than the BCS value, but which clearly and reproducibly closes near the bulk T-c. In conjunction with fits of the conductance spectra, these results are interpreted as direct evidence of two-band superconductivity.

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页数：4

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