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 a-b planes and shows that these superlattices are two-dimensional systems.