화학공학소재연구정보센터
Journal of Crystal Growth, Vol.219, No.4, 385-389, 2000
Growth of large PrBa2Cu3O7-delta single crystals by modified TSSG method using zirconium dioxide crucibles
Bulk PrBa2Cu3O7-delta single crystals of 2.5g weight were seed-grown by modified TSSG technique using yttria stabilized zirconium dioxide crucibles. A chemical composition analysis revealed a visible yttrium substitution (from the seed and crucible material) of Pr atoms to x = 0.2-0.3 in the Pr1-xYxBa2Cu3O7-delta formula. Neutron diffraction and X-ray diffraction measurements showed the block structure of different disorientation along the [0 0 1]- and [1 0 0]-directions. FWHM of the rocking curve on (0 0 6) reflection is 0.9 degrees by neutron diffraction and 0.5 degrees by X-ray diffraction. FWHM of the rocking curve on a (200) reflection is 0.3 degrees by X-ray diffraction. The antiferromagnetic ordering of Pr magnetic moments was found at a temperature T-N = 11 K by neutron diffraction. It was attempted to change the cation distribution and to increase the c-lattice parameter in a Pr123 crystal by fast crystallization. At a cooling rate of 200 K/s the c-parameter increased from 11.68 to 11.75 Angstrom, which is insufficient for a possible appearance of superconductivity in this crystal.