Edge-like planar sandwich-type junctions using a-axis oriented YBa/sub 2/Cu/sub 3/O/sub 7-x//insulator/YBa/sub 2/Cu/sub 3/O/sub 7-x/ trilayers

We have fabricated the in-plane aligned a-axis oriented YBa/sub 2/Cu/sub 3/O/sub 7-x//LaSrGaO/sub 4//YBa/sub 2/Cu/sub 3/O/sub 7-x/ (YBCO/LSGO/YBCO) heteroepitaxial trilayers on LSGO (100) substrates. A LSGO insulating barrier and top YBCO layer were grown on the ion-beam etched in-plane aligned, a-axis oriented YBCO bottom layer. Superconductor-insulator-superconductor edge-like planar sandwich-type junctions using these a-axis oriented YBCO/LSGO/YBCO trilayers had a superconducting transition temperature of 84 K and revealed flux-flow type I-V characteristics.