High-superconducting critical current densities in YBa2Cu3O7/PrBa2Cu3O7 superlattices

Abstract
Well‐ordered [(YBa2Cu3O7)nY/(PrBa2Cu3O7)nPr)]m superlattices with high superconducting critical temperatures were prepared by sequential reactive dc sputtering. The superconducting critical current density at 4.5 K reaches values as high as 1.1×107 A/cm2 for a sample with nY = 2 and nPr = 1 and 3.8×106 A/cm2 for nY = 1 and nPr = 3, indicating that the coupling of the CuO2 layers is not necessary for high‐jc values. The angular dependence jc(φ) is determined by the component of the magnetic field perpendicular to the ab planes and shows that these superlattices are two‐dimensional systems.