TITLE

Persistent currents in Tl-Ba-Ca-Cu-O superconductors

AUTHOR(S)
Grader, G. S.; Gyorgy, E. M.; Van Uitert, L. G.; Grodkiewicz, W. H.; Kyle, T. R.; Eibschutz, M.
PUB. DATE
July 1988
SOURCE
Applied Physics Letters;7/25/1988, Vol. 53 Issue 4, p319
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
We have demonstrated the presence of circulating circumferential currents in toroids of Tl-Ba-Ca-Cu-O superconductors at 77.3 and 90.2 K. The nominal composition was Tl1.5Ba2Ca2Cu3Ox; however, both the x-ray diffraction pattern and the Meissner effect indicate the presence of more than one phase. The circulating current was found to decrease by 27% in 3.8×103 s. The nature of the above time dependence is not consistent with the presence of a simple ohmic resistance but rather indicates that a process such as flux creep is the cause of this decay. An estimated upper limit of the resistivity is 1.3×10-14 Ω cm at 77.3 K.
ACCESSION #
9827507

 

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