YBa2Cu3O7-δ (YBCO) films with high critical current density (Jc) were successfully fabricated on nickel tapes buffered with epitaxial NiO. NiO was prepared on the textured nickel tape by the surface-oxidation epitaxy (SOE) method. We have reported so far a critical temperature (Tc) of 87 K and Jc = 4-6×104 A/cm2 (77 K, 0 T) for the YBCO films on NiO/Ni tapes. To enhance the superconducting properties of the YBCO films on the SOE-grown NiO, depositions of thin oxide cap layers such as YSZ, CeO2, and MgO on NiO were investigation. These oxide cap layers were epitaxially grown on NiO and provided the template for the epitaxial growth of YBCO films. Substantially improved data of Tc = 88 K and Jc = 3×105 A/cm2 (77 K, 0 T) and 1×104 A/cm2 (77 K, H∥c, 4 T) were obtained for YBCO film on NiO, by using a MgO cap layer with a thickness of 50 nm. The method described in this paper is a simple way to produce long YBCO tape conductors with high-Jc values.
ASJC Scopus subject areas
- Condensed Matter Physics