Magnetic relaxation and critical currents of NdBCO coated conductors
Abstract
A magnetic study of the critical current density Jc and magnetic relaxation (`creep') effects in thin NdBa2Cu3O7-δ (NdBCO) superconducting films of thicknesses 0.7 and 2.1 μm was conducted. These films, doped with BaZrO3, were deposited by a PLD process on `IBAD' substrates. The Jc values display broad peaks near the c-axis. This is associated with densely spaced columnar defects distributed about this axis. We analyzed the magnetic relaxation data using the Maley expression for the activation energy U as a function of current density J. The data are described fairly well by the collective creep interpolation formula U=U0[(Jc0/J)^μ-1] with U0, Jc0, and μ treated as fitting parameters.
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2007
- Bibcode:
- 2007APS..MAR.B9008I