Experimental Design and Investigation of Novel Pulsed Laser Deposited Structures for YBCO Based Coated Conductors

Abstract

ABSTRACTThe study of high quality YBa2Cu3O7-x (YBCO) based superconducting films is a fundamental issue to be addressed when dealing with the realization of efficient coated conductors with large current carrying capacity. In this perspective the investigation of innovative buffer layers structures able to allow epitaxial YBCO film grow on metallic substrates and to prevent contamination and degradation issues holds a central role.In this work we thoroughly study the properties of YBCO films grown by means of pulsed lasers deposition on CeO2 template on both bare MgO single crystal and MgO-homoepitaxial/MgO single crystal substrates. Due to its high chemical and temperature stability the MgO reduces the oxygen diffusion effects. On the other hand, the CeO2 layer, pulsed laser deposited, prevents the YBCO film from metallic contamination and facilitates its epitaxial growth. Morphology and crystalline structure of buffer layers and superconductors film are investigated by using scanning electron microscopy (SEM), X-ray and electrons back-scattered diffraction techniques (XRD and EBSD).YBCO films show good critical temperature values (Tc > 87K) with sharp transitions. These encouraging results make our structures promising candidates in the realization of high quality YBCO based coated conductors.