A novel method for the determination of the flux-creep exponent from higher harmonic ac-susceptibility measurements

被引：11
作者：
Schindler, K
Ziese, M
Esquinazi, P
Hochmuth, H
Lorenz, M
Zimmer, K
Brandt, EH
机构：
[1] Univ Leipzig, Div Superconduct & Magnetism, D-04103 Leipzig, Germany
[2] Univ Leipzig, Semicond Phys Grp, D-04103 Leipzig, Germany
[3] Inst Surface Modificat, D-04318 Leipzig, Germany
[4] Max Planck Inst Metallforsch, D-70506 Stuttgart, Germany
来源：
PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS | 2005年 / 417卷 / 3-4期
关键词：
YBa2Cu3O7; Ac-susceptibility; flux creep; critical current density;
D O I：
10.1016/j.physc.2004.10.013
中图分类号：
O59 [应用物理学];
学科分类号：
摘要：
The critical current density and flux-creep activation energy of YBa2C3O7 rings were determined from ac-susceptibility measurements. A novel approach was developed theoretically and experimentally to derive the flux-creep exponent from higher susceptibility harmonics. An alternative method using a scaling approach yielded similar sample-to-sample variations, but qualitatively different values for the flux-creep exponent. This is discussed considering the limits of validity of the logarithmic approximation to the flux-line activation energy. (C) 2004 Elsevier B.V. All rights reserved.
引用
收藏
页码：141 / 149
页数：9
相关论文
共 28 条
[1]   Harmonics of the AC susceptibility as probes to differentiate the various creep models [J].
Adesso, MG ;
Senatore, C ;
Polichetti, M ;
Pace, S .
PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS, 2004, 404 (1-4) :289-292
[2]   Harmonics of the AC susceptibility for the study of I-V curves in melt grown YBCO [J].
Adesso, MG ;
Polichetti, M ;
Pace, S .
PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS, 2004, 401 (1-4) :196-200
[3]   Collective dynamics of a highly dilute vortex lattice in YBa2Cu3O7-δ thin films -: art. no. 134525 [J].
Åkerman, JJ ;
Rao, KV .
PHYSICAL REVIEW B, 2002, 65 (13) :1-5
[4]   Dislocation-mediated creep of highly separated vortices in a-axis-oriented HgBa2CaCu2O6+δ thin films -: art. no. 024526 [J].
Åkerman, JJ ;
Yun, SH ;
Karlsson, UO ;
Rao, KV .
PHYSICAL REVIEW B, 2001, 64 (02)
[5]   Re-entrant behavior of low-field flux creep in c-axis-oriented HgBa2CaCu2O6+δ thin films -: art. no. 184520 [J].
Åkerman, JJ ;
Yun, SH ;
Karlsson, UO ;
Rao, KV .
PHYSICAL REVIEW B, 2001, 64 (18)
[6]   A NEW EXTENDED CRITICAL-STATE MODEL INCLUDING THE LOWER CRITICAL-FIELD AND SCREENING [J].
ARNDT, T ;
SCHAUER, W ;
REINER, J .
PHYSICA C, 1993, 210 (3-4) :417-431
[7]   MAGNETIZATION OF HIGH-FIELD SUPERCONDUCTORS [J].
BEAN, CP .
REVIEWS OF MODERN PHYSICS, 1964, 36 (1P1) :31-+
[8]   THIN SUPERCONDUCTORS IN A PERPENDICULAR MAGNETIC AC FIELD .2. CIRCULAR DISK [J].
BRANDT, EH .
PHYSICAL REVIEW B, 1994, 50 (06) :4034-4050
[9]   Susceptibility of superconductor disks and rings with and without flux creep [J].
Brandt, EH .
PHYSICAL REVIEW B, 1997, 55 (21) :14513-14526
[10]   THIN SUPERCONDUCTORS IN A PERPENDICULAR MAGNETIC AC FIELD - GENERAL FORMULATION AND STRIP GEOMETRY [J].
BRANDT, EH .
PHYSICAL REVIEW B, 1994, 49 (13) :9024-9040
123