An increase in the critical current of superconducting composites upon implantation of iron ions

The results of studying the effect of ion irradiation (Fe$^{2+}$ $E$ = 5.6 MeV) in the modes of creating radiation defects and implantation on the critical current of high-temperature superconducting (HTS) composites are presented. An analysis was made of both the integral critical current obtained from measurements of the total magnetization of the samples and the local critical current determined from the data of scanning Hall magnetometry. It is shown that at the same ion fluence $\Phi$ = 2 $\cdot$ 10$^{13}$ cm$^{-2}$, an increase in the critical current $J_c$ is observed in the ion implantation regime, while in the regime of radiation defects, a slight drop in $J_c$ is observed. This circumstance indicates an enhancement of pinning due to the additional magnetic interaction of Abrikosov vortices with magnetic ions implanted in the HTS layer.