Superconducting energy gap distribution of MgB2 investigated by point-contact spectroscopy

被引:34
作者
Laube, F
Goll, G
Hagel, J
von Höhneysen, H
Ernst, D
Wolf, T
机构
[1] Univ Karlsruhe, Inst Phys, D-76128 Karlsruhe, Germany
[2] Forschungszentrum Karlsruhe, Inst Festkorperphys, D-76021 Karlsruhe, Germany
来源
EUROPHYSICS LETTERS | 2001年 / 56卷 / 02期
关键词
D O I
10.1209/epl/i2001-00519-4
中图分类号
O4 [物理学];
学科分类号
0702 ;
摘要
We performed point-contact spectroscopy on the binary superconductor MgB2. The differential conductance shows gap-related structures which vary in width and position from contact to contact. The distribution of energy gaps shows a distinct accumulation around 1.7 and 7 meV which is associated with the occurrence of a small and a large energy gap in MgB2. While with increasing T the structure in dI/dV associated with the small gap is present up to T-c, in magnetic field it is suppressed well below B-c2.
引用
收藏
页码:296 / 301
页数:6
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