Irreversibility line and critical current densities of an oxycarbonate thin film Ba2Ca3Cu4CO3O8

The magnetic behaviour of the 58 K superconductor oxycarbonate thin film, which consists of an intergrowth of several members of a family with agreement composition (CaCuO2)m(Ba2CuCO3O2)n has been studied. Its pinning properties in terms of critical current densities and irreversibility line have been established using their hysteresis cycles. Typical Jc was calculated to approximately 105 A cm-2 at 5 K in zero field. Finally, the irreversibility line is compared to those obtained by Kumakura et al. (1994) on bulk oxycarbonate superconductors synthesized at high pressure.