Comparison of Y<sub>2</sub>Ba<sub>4</sub>CuBiOy Nanoparticles with CeO<sub>2</sub> Doping on the Levitation Force of Single Domain YBCO Bulk Superconductor by TSIG Process

Abstract

The top-seeded infiltration and growth process (TSIG) is very effective method for the preparation of YBa 2 Cu 3 O 7−x (YBCO) bulk superconductors. In order to improve the levitation force of the samples, a series of single domain YBCO bulk superconductors with different ratios of nanoscale Y 2 Ba 4 CuBiO y (YBi2411) inclusions in the solid phase pellet is successfully fabricated by the TSIG technique on the basis of previous research. In the present work, the results of YBCO bulk superconductors with YBi2411 and CeO 2 (1 wt%) codoping system indicate that, the optimum doping of YBi2411 is 2 wt%, the size of Y211 particles is reduced compared with the samples without CeO 2 doping; the largest levitation force is about 15 N obtained in the samples with optimum YBi2411, which is about two times higher than that of the sample without CeO 2 doping. The results are very helpful for the fabrication of high quality single domain YBCO bulk superconductors.