Temperature and field dependence of the anisotropy of MgB2 -: art. no. 167004

被引：268

作者：

Angst, M ^{[1
]}

Puzniak, R

Wisniewski, A

Jun, J

Kazakov, SM

Karpinski, J

Roos, J

Keller, H

机构：

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

[2] Polish Acad Sci, Inst Phys, PL-02668 Warsaw, Poland

[3] Univ Zurich, Inst Phys, CH-8057 Zurich, Switzerland

来源：

PHYSICAL REVIEW LETTERS | 2002年 / 88卷 / 16期

关键词：

D O I：

10.1103/PhysRevLett.88.167004

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

The anisotropy gamma of the superconducting state of high quality single crystals of MgB2 was determined, using torque magnetometry with two different methods. The anisotropy of the upper critical field was found to be temperature dependent, decreasing from gamma similar or equal to 6 at 15 K to 2.8 at 35 K. Reversible torque data near T-c reveal a field dependent anisotropy, increasing nearly linearly from gamma similar or equal to 2 in zero field to 3.7 in 10 kOe. The unusual temperature dependence is a true bulk property and can be explained by nonlocal effects of anisotropic pairing and/or the k dependence of the effective mass tensor.

引用

页码：1670041 / 1670044

页数：4

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