DC and AC Shielding Properties of Bulk High-Tc Superconducting Tubes
- Resource Type
- Periodical
- Authors
- Fagnard, J.-F.; Denis, S.; Lousberg, G.; Dirickx, M.; Ausloos, M.; Vanderheyden, B.; Vanderbemden, P.
- Source
- IEEE Transactions on Applied Superconductivity IEEE Trans. Appl. Supercond. Applied Superconductivity, IEEE Transactions on. 19(3):2905-2908 Jun, 2009
- Subject
- Fields, Waves and Electromagnetics
Engineered Materials, Dielectrics and Plasmas
Magnetic shielding
Magnetic field measurement
Magnetic flux
Magnetic properties
Superconducting coils
Attenuation measurement
Frequency measurement
Superconducting magnets
Ceramics
Hall effect devices
Bi-2223 cylinder
magnetic shielding
- Language
- ISSN
- 1051-8223
1558-2515
2378-7074
We have studied numerically and experimentally the magnetic flux penetration in high-$T_{c}$ superconducting tube subjected to a uniform magnetic field parallel to its long axis. This study is carried in view of designing low-frequency magnetic shields by exploiting the diamagnetic properties of high-$T_{c}$ superconducting ceramics. We have measured the field attenuation for applied magnetic fields in the frequency range 5 mHz–0.1 Hz by Hall probe measurements and at audio frequencies using a sensing coil. A simple 1D analysis using the Kim critical state model was found to be able to reproduce the experimental data satisfactorily. We have also determined the phase shift between the internal and the applied field both experimentally and numerically. Finally, we have studied the sweep rate dependence of the magnetic shielding properties, using data recorded either at several constant sweep rates ${\rm d}B/{\rm d}t$ or at several AC fields of various amplitudes and frequencies. Both methods agree with each other and lead to a $n$ -value of the $E\sim J^{\rm n}$ law equal to $\sim$40 at 77 K.