TY - JOUR

T1 - Observation of Flux Distribution on the Surface of MPMG-processed YBCO

AU - Higuchi, T.

AU - Sakai, N.

AU - Murakami, M.

AU - Hashimoto, M.

N1 - Funding Information:
This work was partially supported by NED0 for the R&D Science and Technology Frontier Program.

PY - 1995/6

Y1 - 1995/6

N2 - A macroscopic observation of a magnetic flux distribution on the surface of a superconducting bulk material was performed. First, a single-domained thin rectangular YBCO sample (10 mm×10mm×1mm) was field-cooled in liquid nitrogen. After the applied field was turned off, a field distribution in the area of 10mm×10mm was mapped by scanning the sample surface at intervals of 0.5mm using a Hall probe fixed to a XY-stage. The obtained field distribution was visualized into a three-dimensional distribution map and a two-dimensional contour graph. The overall shape of the field distribution had a four-fold symmetry reflected by the sample geometry. Next, assuming that the critical current density Jcis independent of the field strength, a field distribution generated by square current loops was calculated numerically. The intragranular Jcwas estimated to be 2.6×104A/cm2 (77K, 0T) by fitting the calculated profile to the measured profile. Finally, it is found that the measurement of field distributions on the surface of a superconductor using a Hall probe is applicable to an estimation of an ntragranular Jcfor a superconductor without destroying the samples.

AB - A macroscopic observation of a magnetic flux distribution on the surface of a superconducting bulk material was performed. First, a single-domained thin rectangular YBCO sample (10 mm×10mm×1mm) was field-cooled in liquid nitrogen. After the applied field was turned off, a field distribution in the area of 10mm×10mm was mapped by scanning the sample surface at intervals of 0.5mm using a Hall probe fixed to a XY-stage. The obtained field distribution was visualized into a three-dimensional distribution map and a two-dimensional contour graph. The overall shape of the field distribution had a four-fold symmetry reflected by the sample geometry. Next, assuming that the critical current density Jcis independent of the field strength, a field distribution generated by square current loops was calculated numerically. The intragranular Jcwas estimated to be 2.6×104A/cm2 (77K, 0T) by fitting the calculated profile to the measured profile. Finally, it is found that the measurement of field distributions on the surface of a superconductor using a Hall probe is applicable to an estimation of an ntragranular Jcfor a superconductor without destroying the samples.

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U2 - 10.1109/77.402933

DO - 10.1109/77.402933

M3 - Article

AN - SCOPUS:0029323979

SN - 1051-8223

VL - 5

SP - 1818

EP - 1821

JO - IEEE Transactions on Applied Superconductivity

JF - IEEE Transactions on Applied Superconductivity

IS - 2

ER -