Process and Mechanism of Growth of YBa_2Cu_3O_(6+x) Single Crystal by the Pulling Method

摘要

Continuous growth of YBa_2Cu_3O_(6+x)(Y123) single crystals was achieved by the modified pulling method using BaO+CuO(3:5) solvent and Y_2BaCuO_5(Y211) solute. Y211 solid was placed at the bottom of the crucible. Temperature was set ten degrees higher at the bottom than on the surface of the solution. The crystal rotation speed was 120 rpm at first; but as the crystal radius increased, it was reduced to prevent increasing the interface temperature. The maximum crystal growth rate was about 0.2 mm/h. The crystal growth direction was controlled by the seed crystal direction. Two-dimensional numerical simulation was performed using a finite-difference method by a supercomputer to investigate the solution flow and temperature distribution.