Comparative study of magnetic properties between melt-textured and single crystalline Y-Ba-Cu-O

Abstract We studied magnetic properties of a melt-textured Y–Ba–Cu–O with Y 2 BaCuO 5 inclusions and a single crystalline YBa 2 Cu 3 O y grown by a crystal pulling technique by changing oxygen annealing conditions with the emphasis placed on the effect of doping level on flux pinning. Magnetization hysteresis loop measurements at 20 K and 77 K showed that the critical currents of the melt-textured sample were three times as large as those of a single crystal, which confirms the contribution of Y 2 BaCuO 5 to pinning enhancement. In order to enhance flux pinning, it is important to introduce effective pinning centers in the good matrix with sufficiently large oxygen content.