DocumentCode :
843783
Title :
Nonlinear magnetic diffusion in single-domain YBCO cylinders under pulsed field conditions
Author :
Askew, Thomas R. ; O´Daniel, Jennifer C. ; Weber, Jonathan M. ; Cha, Y.S.
Author_Institution :
Phys. Dept., Kalamazoo Coll., MI, USA
Volume :
15
Issue :
2
fYear :
2005
fDate :
6/1/2005 12:00:00 AM
Firstpage :
3758
Lastpage :
3761
Abstract :
A step-function increase in magnetic field has been applied to various single-domain Y-Ba-Cu-O rings and disks at 77 K. The magnetic field in the center of these structures exhibits an exponential approach to an equilibrium value, as predicted by simple diffusion theory. The measured time constants are in the millisecond range and show nonlinear behavior, as predicted in recently advanced theories of magnetic diffusion under flux flow conditions. Measurements of trapped magnetic field, critical current density, and current-voltage (I-V) characteristics are compared to results obtained by measurement of magnetic diffusion. The single-domain structures are intended for use in penetration-type fault current limiters, an application where the magnetic diffusion time constants have a strong influence on device design.
Keywords :
barium compounds; critical current density (superconductivity); diffusion; high-temperature superconductors; magnetic flux; penetration depth (superconductivity); yttrium compounds; 77 K; Y-Ba-Cu-O; critical current density; current-voltage characteristics; exponential approach; flux flow condition; magnetic flux penetration; magnetic shielding; nonlinear magnetic diffusion; penetration-type fault current limiters; pulsed field conditions; single-domain YBCO cylinders; single-domain structures; step function; trapped magnetic field; Critical current density; Current measurement; Density measurement; Fault current limiters; Fluid flow measurement; Magnetic field measurement; Magnetic flux; Nonlinear magnetics; Time measurement; Yttrium barium copper oxide; Magnetic diffusion; magnetic flux penetration; magnetic shielding; single-domain YBCO cylinders;
fLanguage :
English
Journal_Title :
Applied Superconductivity, IEEE Transactions on
Publisher :
ieee
ISSN :
1051-8223
Type :
jour
DOI :
10.1109/TASC.2005.849424
Filename :
1440489
Link To Document :
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