Reliable 4.8 T Trapped Magnetic Fields In Gd-Ba-Cu-O Bulk Superconductors Using Pulsed Field Magnetization

A robust and reliable in-situ magnetization method is essential for exploiting the outstanding magnetic flux trapping ability of bulk superconductors in practical applications. We report a 4.8 T peak trapped magnetic field, B-T, achieved at 30 K in a 36 mm diameter GdBa2Cu3O7-delta-Ag bulk superconductor using pulsed field magnetization (PFM). To realize this, we have developed a reliable two-step multi-pulse PFM process based on understanding and exploiting the avalanche-like flux jump phenomenon observed in these materials. The magnitude of the applied pulsed magnetic field (B-a) necessary to trap 4.8 T was merely 5.29 T, corresponding to a remarkable magnetization efficiency (B-T/B-a) of 90%.