A superconducting article includes a substrate having a biaxially textured surface, and an epitaxial biaxially textured superconducting film supported by the substrate. The epitaxial superconducting film includes particles of Ba.sub.2RENbO.sub.6 and is characterized by a critical current density higher than 1 MA/cm.sup.2 at 77K, self-field. In one embodiment the particles are assembled into columns. The particles and nanocolumns of Ba.sub.2RENbO.sub.6 defects enhance flux pinning which results in improved critical current densities of the superconducting films. Methods of making superconducting films with Ba.sub.2RENbO.sub.6 defects are also disclosed.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
 The United States Government has rights in this invention pursuant to Contract No. DE-AC05-00OR22725 between the United States Department of Energy and UT-Battelle, LLC.