Fabrication and superconducting properties of ternary REBa2Cu3Oy thin films

Thin films of ternary REBa2Cu3Oy (RE = Y0.33R0.33Nd0.33, R = Ho, Gd, and Eu ) were grown by pulsed laser deposition technique. The films showed an onse t of T-c around 90 K and a sharp transition with a width of similar to1.5 K . Microstructural investigations using AFM revealed that the morphology of the grain growth is mainly controlled by step growth mechanism. The individ ual grains are observed to merge to form elongated grains. X-ray diffractio n pattern showed the grains to be oriented along c-axis. Magnetisation meas urements using SQUID magnetometer displayed highest J(c), 3.5 x 10(7) A/cm( 2) at 77 K, 0 T field in (Y0.33Ho0.33Nd0.33)Ba2Cu3Oy films, where the diffe rence in ionic radii between the RE atoms is maximum. (C) 2002 Elsevier Sci ence B.V. All rights reserved.