Full Vector Magnetic Field Critical Current Characterization of Coated Conductors Deposited on Solution Deposition Planarized IBAD Templates

Abstract

Second generation high temperature super-conductor (HTS) wire consists of metal substrate tapes textured with intermediate buffer layers that are coated with a superconducting layer. The applications of these coated conductors require a high current in magnetic fields that are not restricted to a narrow range of angles. Ion beam assisted deposition (IBAD) template tilt, in combination with REBCO vapor deposition, results in asymmetric sample growth. This requires Vector Magnetic Field (VMF) measurement over 180 degrees to be fully described. We have developed a piece wise characterization and analysis method of the VMF using a number of Ic scaling models. Solution Deposition Planarization (SDP) permits REBCO film deposition on 100 nm rms roughness substrates. To test buffer layer effects on film growth, with and without SDP, superconducting films were deposited at Superconductor Technologies, Inc. by co-evaporation of REBCO on IBAD buffer layer templates from Los Alamos. Critical current measurements in VMF up to a magnitude of ~ 0.9 Tesla show behaviors traceable to the effects of buffer layer template on pinning. The ability to discriminate between buffer layers based on in-field Ic behavior is a useful technique for the optimization of buffer layers for future REBCO film deposition.