CRYSTAL-GROWTH OF SMBA2CU3O7-X UNDER LOW-OXYGEN PARTIAL-PRESSURE

Single crystals of SmBa2Cu3O7-x (Sm-123) have been successfully grown by a modified top-seeded solution growth (TSSG) method under a 1% oxyg en-partial-pressure atmosphere (P(O-2) = 0.01 atm). Solid Sm2BaCuO5 (S m-211) solute and Ba-Cu-O solvent (Ba:Cu = 3:5) were put in a Sm2O3 cr ucible. The temperature of Sm-123 crystal growth under P(O-2) = 0.01 a tm was approximately 40 degrees C lower than that under an air atmosph ere. The Sm-123 as-grown crystals were confirmed to have the SmBa2Cu3O 6 tetragonal structure by X-ray structure analyses. The transport prop erties of the Sm-123 single crystals annealed in an oxygen gas flow we re measured by the direct-current four-contact method, both in the nb- plane and along the c-axis. The superconductive transition temperature was 92.8 K, and the transition width was 0.6 K. The ratio of the resi stivities along the c-axis/a(b)-axis was similar to 17.5 just above T- c.