Enhanced critical current density in optimized high-temperature superconducting bilayer thin films

The superconducting and structural properties of bilayer thin films based on YBa2Cu3O 7-x / YBa2Cu3O 7-x +6%BaZrO3 heterstructures have been studied. In a broad range of magnetic field strengths and temperatures, the optimal bilayer film comprises 30% YBCO at the substrate interface and 70% YBCO+6%BZO on the top. The critical current density measured for the optimal bilayer structure is shown to outperform the corresponding single layer films up to almost 60%. The obtained results are comprehensively discussed in the light of our previously published theoretical framework (Rivasto et al 2023 J. Phys.: Condens. Matter 35 075701:1-10). We conclude that the bilayering provides an efficient and easily applicable way to further increase the performance and applicability of high-temperature superconductors in various applications. Consequently, the bilayer films should be seriously considered as candidates for the upcoming generation of coated conductors.