EVALUATION OF Sr2YSbO6 AS A NEW SUBSTRATE FOR YBa2Cu3O7-δ SUPERCONDUCTOR THIN FILMS

Abstract

A complex perovskite oxide Sr 2 YSbO 6 has been synthesized by solid-state reaction. X-ray diffraction (XRD) pattern reveals that Sr 2 YSbO 6 has an ordered complex cubic structure characteristic of A 2 BB ' O 6 crystalline structure with lattice constant a=8.2561 Å which has a fairly good lattice matching (lattice mismatch of the order of 8%) with YBa 2 Cu 3 O 7-δ. Energy dispersive X-ray (EDX) analysis shows that Sr 2 YSbO 6 is free of impurity traces. The chemical stability of Sr 2 YSbO 6 with YBa 2 Cu 3 O 7-δ superconducting has been studied by X-ray diffraction and magnetic measurements on Sr 2 YSbO 6– YBa 2 Cu 3 O 7-δ composites. XRD patterns of the composite show that all the XRD peaks could be indexed for either Sr 2 YSbO 6 or YBa 2 Cu 3 O 7-δ with no extra peak detectable. This implies that YBa 2 Cu 3 O 7-δ and Sr 2 YSbO 6 remain as two different separate phases in the composite with no chemical interaction. Magnetic measurements show that superconducting transition temperature of pure YBa 2 Cu 3 O 7-δ and Sr 2 YSbO 6– YBa 2 Cu 3 O 7-δ composites is 90 K. These favorable characteristics of Sr 2 YSbO 6 show that it can be used as a potential substrate material for fabrication of YBa 2 Cu 3 O 7-δ superconducting films.