We show that the Brick Wall Model [L.N. Bulaevskii et al., Phys. Rev. B 45, 2545 (1992)], developed to explain the high field critical current (Jc) of superconducting tapes, explains the observed minimum of Jc close to Hc1 of the grains in polycrystalline materials. The quantitative agreement when fitting Jc of a well-characterized Gd1Ba2Cu3O7 ceramic shows that the minimum at HC1 is determined by the field dependence of the magnetization of the grains.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering