Effect of oxide dopants on the superconducting properties of YBCO superconductor

YBCO superconductors with different contents were prepared by a unique method, called a partial melting process, to study the effect of cerium oxide on their electromagnetic properties and superconducting mechanism. Microstructure observations by electron microscopy and chemical analysis by X-ray and electron micro-probe analyses showed that the cerium oxide formed a BaCeO3 phase. which separately existed from a YBCO phase. The critical temperature of the YBCO superconductor was not predominantly dependent upon the cerium oxide phase. The maximum magnetism was observed by adding 3% cerium oxide. The addition of cerium oxide formed a pinning center of magnetic flux due to the BaCeO3 phase, which was related to a change for the electromagnetic properties of the YBCO superconductor. (C) 2008 Published by Elsevier B.V.