Mathematical modeling of the magnetic properties of axisymmetric hard superconductors of the second kind in the Kim model

Authors perform mathematical modeling of magnetic properties, such as current distribution, intrinsic magnetic field and magnetization of a number of axisymmetric superconductors of the second kind, for example, of a sphere with the dependence of the critical current density on the local magnetic field in the Kim model. The simulation is based on equation that is integral with respect to coordinate and differential with respect to time. The equation describes time evolution of the critical current density and is solved numerically for a uniformly varying external magnetic field. The shape of the sample is set using a distorted rectangular irregular mesh with compaction to the edges of the sample. While solving the equation of current motion, the total magnetic field iscalculated at the points of the superconductor to calculate the value of the critical current density. In the article, the obtained solutions are used to visualize the current distribution in the volume of a superconductor and to construct magnetization hysteresis loops. Also, thanks to the calculations of the magnetic field in the center of the sample, the dependencies of the total penetration field for samples with different aspect ratios are obtained.

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STUDY OF THE TEXTURING IN BSCCO-AG TAPES THROUGH MAGNETIC MEASUREMENTS

International Journal of Modern Physics B ◽

10.1142/s0217979200003472 ◽

2000 ◽

Vol 14 (25n27) ◽

pp. 3159-3164

Author(s):

C. FERDEGHINI ◽

M. R. CIMBERLE ◽

G. GRASSO ◽

P. GUASCONI ◽

A. MALAGOLI ◽

...

Keyword(s):

Magnetic Field ◽

Critical Current Density ◽

Critical Current ◽

Current Density ◽

Magnetic Measurements ◽

Texture Evolution ◽

Rolling Direction ◽

Longitudinal Direction ◽

Magnetic Method ◽

Superconducting Compounds

We have developed a method that allows, by a simple set of magnetic measurements, to study the texturing of the grains inside a BSCCO-Ag tape. Because the texture is anisotropic we define the angle ϑ L that identifies the mean grain misalignment angle with respect to the tape surface in longitudinal direction (i.e. rolling direction) and the angle ϑ T in transverse direction. The technique is based on the assumption that, because of the very high anisotropy of the critical current density in BSCCO superconducting compounds, the magnetic moment is essentially generated by the current circulating in the a-b planes of the BSCCO grains. The different magnetisation cycles, measured when the orientation of the magnetic field with respect to the tape surface is changed, depend only on the grain orientation inside the tape, which determines the effective magnetic field component normal to the a-b planes of the grains. Here we present the texture evolution of the BSCCO grains inside silver sheated multifilamentary tape starting from the initial steps of the mechanical deformation up to the final heating stage. The results obtained from the magnetic method are compared with those obtained with other methods, i.e. X-ray diffraction and critical current density anisotropy. Also results obtained on samples prepared in different way will be presented.

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The Critical Current Density and the Curvature of the Magnetic Field in Epitaxial YBaCuO Films

physica status solidi (b) ◽

10.1002/pssb.2221700220 ◽

1992 ◽

Vol 170 (2) ◽

pp. 549-562 ◽

Cited By ~ 19

Author(s):

D. Glatzer ◽

A. Forkl ◽

H. Theuss ◽

H. U. Habermeier ◽

H. Kronmüller

Keyword(s):

Magnetic Field ◽

Critical Current Density ◽

Critical Current ◽

Current Density ◽

The Magnetic Field

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Effect of magnetic field on the resistive transition and critical current density of Y-Ba-Cu-O/Ag rolled tapes

10.1063/1.40269 ◽

1991 ◽

Author(s):

G. Swaminathan ◽

S. Rajendra Kumar ◽

N. Ramadas ◽

K. Venugopal ◽

K. A. Durga Prasad ◽

...

Keyword(s):

Magnetic Field ◽

Critical Current Density ◽

Critical Current ◽

Current Density ◽

Resistive Transition

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Magnetic-Field and Temperature Dependence of the Critical Current Density in High-Quality Bi2Sr2Ca2Cu3Ox Thin Films

Advances in Superconductivity V ◽

10.1007/978-4-431-68305-6_110 ◽

1993 ◽

pp. 493-496 ◽

Cited By ~ 3

Author(s):

Hirofumi Yamasaki ◽

Kazuhiro Endo ◽

Shin Kosaka ◽

Masaichi Umeda ◽

Shunji Misawa ◽

...

Keyword(s):

Magnetic Field ◽

Thin Films ◽

Critical Current Density ◽

Temperature Dependence ◽

Critical Current ◽

Current Density ◽

High Quality

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Effect of Heat Treatment on Critical Current Density–Magnetic Field Curve for YBa2Cu3O7-δSingle Crystal and Its Microstructure

Japanese Journal of Applied Physics ◽

10.1143/jjap.39.5822 ◽

2000 ◽

Vol 39 (Part 1, No. 10) ◽

pp. 5822-5827 ◽

Cited By ~ 7

Author(s):

Akihiro Oka ◽

Satoshi Koyama ◽

Teruo Izumi ◽

Yuh Shiohara ◽

Junko Shibata ◽

...

Keyword(s):

Magnetic Field ◽

Heat Treatment ◽

Critical Current Density ◽

Critical Current ◽

Current Density

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Estimation of Local Current Transport Properties in Thin Film Superconductor Based on Scanning Hall-probe Microscopy

MRS Proceedings ◽

10.1557/opl.2012.1587 ◽

2012 ◽

Vol 1434 ◽

Cited By ~ 1

Author(s):

Kohei Higashikawa ◽

Kei Shiohara ◽

Masayoshi Inoue ◽

Takanobu Kiss ◽

Masateru Yoshizumi ◽

...

Keyword(s):

Magnetic Field ◽

Thin Film ◽

Critical Current Density ◽

Electric Field ◽

Critical Current ◽

Current Density ◽

Limiting Factors ◽

Hall Probe ◽

Scanning Hall Probe Microscopy ◽

Field Criterion

ABSTRACTTo enhance a global critical current in a superconductor, it is indispensable to understand current limiting factors and their influence on such a critical current. From this point of view, we have investigated in-plane distribution of local critical current density and its electric field criterion in a thin-film superconductor by using scanning-Hall probe microscopy. In a remanent state, after the application of sufficiently high magnetic field to a sample, current flows at critical current density according to the critical state model. Such distribution of current density was estimated from that of measured magnetic field using the Biot-Savart law. Furthermore, the corresponding electric field criterion was evaluated from the relaxation of such remanent magnetic field by considering Faraday’s law. This means that we could estimate in-plane distribution of local critical current density as a function of electric field criterion in a nondestructive manner. This characterization method would be very helpful for finding current limiting factors in a thin-film superconductor and their influence on its global current density versus electric field properties which would usually be obtained by four-probe method.

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