CONTINUOUS CRYSTAL-GROWTH OF YBA2CU3O7-X BY THE MODIFIED TOP-SEEDED CRYSTAL PULLING METHOD

Continuous growth of YBa2Cu3O7-x (Y123) crystals was achieved by a pulling method using a BaO-CuO solution with the solid Y2BaCuO5 (Y211) as a solute. A suitable crucible was also investigated, and an yttria crucible was found to be the best selection for this method. The growth was performed in an ambient atmosphere at about 1000-degrees-C. When a textured Sm-Ba2Cu3O7-delta (Sm123) rod was used as a seed crystal, the Y123 crystal grew epitaxially from the seed. The grown crystal contained no Y211 particles; however, it had a twin structure near the surface, which had been formed during the in situ cooling process. The temperature dependence of the resistance was metallic in both directions, along the c-axis and in the ab-plane after appropriate oxygen annealing.