High-field critical current enhancement by irradiation induced correlated and random defects in (Ba0.6K0.4)Fe2As2
journal contributionposted on 12.04.2016, 00:00 by K. J. Kihlstrom, L. Fang, Y. Jia, B. Shen, A. E. Koshelev, U. Welp, G. W. Crabtree, W. K. Kwok, A. Kayani, S. F. Zhu, H. H. Wen
Mixed pinning landscapes in superconductors are emerging as an effective strategy to achieve high critical currents in high, applied magnetic fields. Here, we use heavy-ion and proton irradiation to create correlated and point defects to explore the vortex pinning behavior of each and combined constituent defects in the iron-based superconductor Ba0.6K0.4Fe2As2 and find that the pinning mechanisms are non-additive. The major effect of p-irradiation in mixed pinning landscapes is the generation of field-independent critical currents in very high fields. At 7 T ‖ c and 5 K, the critical current density exceeds 5 MA/cm2.