An effective substrate surface decoration to YBCO films by multiphase nanoparticles

• We find a new way to solve particles agglomeration ---Multiphase codeposition.
• Ce0.15/Zr0.85O2 can form high quality multiphase nanoparticles.
• Single phase particles ZrO2 and YSZ have the same pinning performance to YBCO.
• A high pinning property in YBCO films are observed from CZO decorated sample.

Three types of nanodots were deposited on the surface of single crystal LaAlO3(LAO) substrates before preparing YBCO films. By comparing with different interfacial nanodots, it was found that ZrO2 and Y0.15Zr0.85O2 (YSZ) interfacial nanodots have a similar size, shape, and density as well as distribution so that they have a same and weaker effect on the pinning ability of the YBCO film. However, CeO2/ZrO2 = 0.15/0.85 (CZO) has a different character with a small size, large density and uniform distribution. Especially, CZO interfacial nanodots are the most effective to enhance Jc values of YBCO films in applied magnetic field. At 77 K and 3 T, the Jc value of YBCO film with CZO interfacial nanodots decorating is 12 times of that of pure YBCO. A further research indicated that the high performance was due to multiphase. Besides, the advantages of multiphase nanoparticles are more prominent as increasing the applied magnetic field and temperature.