Fermi surface topology and vortex state in MgB2

被引：9

作者：

Dahm, T ^{[1
]}

Graser, S ^{[1
]}

Schopohl, N ^{[1
]}

机构：

[1] Univ Tubingen, Inst Theoret Phys, D-72076 Tubingen, Germany

来源：

PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS | 2004年 / 408卷

关键词：

magnesium diboride; upper critical field; vortex state; specific heat;

D O I：

10.1016/j.physc.2004.02.152

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

Based on a detailed modeling of the Fermi surface topology of MgB2 we calculated the anisotropy of the upper critical field B-c2 within the two gap model. The sigma-band is modeled as a distorted cylinder and the pi-band as a half-torus, with parameters determined from bandstructure calculations. Our results show that the unusual strong temperature dependence of the B-c2 anisotropy, that has been observed recently, can be understood due to the small c-axis dispersion of the cylindrical Fermi surface sheets and the small interband pairing interaction as obtained from bandstructure calculations. We calculate the magnetic field dependence of the density of states within the vortex state for field in C-axis direction and compare with recent measurements of the specific heat on MgB2 single crystals. (C) 2004 Elsevier B.V. All rights reserved.

引用

页码：336 / 337

页数：2

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