Strongly enhanced current densities in superconducting coated conductors of YBa2Cu3O7–x + BaZrO3

There are numerous potential applications for superconducting tapes based on YBa₂Cu₃O_7–x (YBCO) films coated onto metallic substrates¹. A long-established goal of more than 15 years has been to understand the magnetic-flux pinning mechanisms that allow films to maintain high current densities out to high magnetic fields². In fact, films carry one to two orders of magnitude higher current densities than any other form of the material³. For this reason, the idea of further improving pinning has received little attention. Now that commercialization of YBCO-tape conductors is much closer, an important goal for both better performance and lower fabrication costs is to achieve enhanced pinning in a practical way. In this work, we demonstrate a simple and industrially scaleable route that yields a 1.5–5-fold improvement in the in-magnetic-field current densities of conductors that are already of high quality.