Temperature-dependent anisotropy of the penetration depth and coherence length of MgB2 -: art. no. 097005

被引：100

作者：

Fletcher, JD

Carrington, A

Taylor, OJ

Kazakov, SM

Karpinski, J

机构：

[1] Univ Bristol, HH Wills Phys Lab, Bristol BS8 1TL, Avon, England

[2] ETH, Festkorperphys Lab, CH-8093 Zurich, Switzerland

来源：

PHYSICAL REVIEW LETTERS | 2005年 / 95卷 / 09期

基金：

英国工程与自然科学研究理事会;

关键词：

D O I：

10.1103/PhysRevLett.95.097005

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

We report measurements of the temperature-dependent anisotropies (gamma(lambda) and gamma(xi)) of both the London penetration depth lambda and the upper critical field of MgB2. Data for gamma(lambda)=lambda(c)/lambda(a) was obtained from measurements of lambda(a) and lambda(c) on a single crystal sample using a tunnel diode oscillator technique. gamma(xi)=H-c2(perpendicular to c)/H-c2(parallel to c) was deduced from field-dependent specific heat measurements on the same sample. gamma(lambda) and gamma(xi) have opposite temperature dependencies, but close to T-c tend to a common value (gamma(lambda)similar or equal to gamma(xi)=1.75 +/- 0.05). These results are in good agreement with theories accounting for the two-gap nature of MgB2.

引用

收藏

页数：4

相关论文

共 28 条

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

Angst, M ;

Puzniak, R ;

Wisniewski, A ;

Jun, J ;

Kazakov, SM ;

Karpinski, J ;

Roos, J ;

Keller, H .

PHYSICAL REVIEW LETTERS, 2002, 88 (16) :1670041-1670044

[2] Phenomenological two-gap model for the specific heat of MgB [J].

Bouquet, F ;

Wang, Y ;

Fisher, RA ;

Hinks, DG ;

Jorgensen, JD ;

Junod, A ;

Phillips, NE .

EUROPHYSICS LETTERS, 2001, 56 (06) :856-862

[3] Multiband model for tunneling in MgB2 junctions -: art. no. 180517 [J].

Brinkman, A ;

Golubov, AA ;

Rogalla, H ;

Dolgov, OV ;

Kortus, J ;

Kong, Y ;

Jepsen, O ;

Andersen, OK .

PHYSICAL REVIEW B, 2002, 65 (18) :1805171-1805174

[4] Magnetic penetration depth of MgB2 [J].

Carrington, A ;

Manzano, F .

PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS, 2003, 385 (1-2) :205-214

[5] Absence of nonlinear Meissner effect in YBa2Cu3O6.95 [J].

Carrington, A ;

Giannetta, RW ;

Kim, JT ;

Giapintzakis, J .

PHYSICAL REVIEW B, 1999, 59 (22) :14173-14176

[6] Field dependence of the specific heat of single-crystal HgBa2Ca2Cu3O8+delta [J].

Carrington, A ;

Marcenat, C ;

Bouquet, F ;

Colson, D ;

Bertinotti, A ;

Marucco, JF ;

Hammann, J .

PHYSICAL REVIEW B, 1997, 55 (14) :R8674-R8677

[7]

CHANDRASEKHAR BS, 1993, ANN PHYS-LEIPZIG, V2, P535, DOI 10.1002/andp.19935050604

[8] Effects of two-band superconductivity on the flux-line lattice in magnesium diboride [J].

Cubitt, R ;

Eskildsen, MR ;

Dewhurst, CD ;

Jun, J ;

Kazakov, SM ;

Karpinski, J .

PHYSICAL REVIEW LETTERS, 2003, 91 (04)

[9] Experimental evidence for anisotropic double-gap behavior in MgB2 -: art. no. 157002 [J].

Cubitt, R ;

Levett, S ;

Bud'ko, SL ;

Anderson, NE ;

Canfield, PC .

PHYSICAL REVIEW LETTERS, 2003, 90 (15) :4

[10] Fermi surface topology and the upper critical field in two-band superconductors:: Application to MgB2 -: art. no. 017001 [J].

Dahm, T ;

Schopohl, N .

PHYSICAL REVIEW LETTERS, 2003, 91 (01)