High-T/sub c/ SNS edge junctions with integrated YBa/sub 2/Cu/sub 3/O/sub x/ groundplanes

Abstract

We have fabricated high-T/sub c/ SNS weak links in an edge geometry with integrated YBa/sub 2/Cu/sub 3/O/sub x/ (YBCO) groundplanes and SrTiO/sub 3/ insulators, using a process which incorporates six epitaxial layers, including a Co-doped-YBCO normal-metal interlayer. The SNS edge junctions were produced using films deposited by both off-axis sputtering and pulsed laser deposition. These devices exhibit tight J/sub c/ spreads and high I/sub c/R/sub n/ products in a current density regime well-suited for SFQ circuit fabrication. We also describe results on SNS junctions fabricated in a novel "slot" geometry, designed to reduce junction and interconnect inductances.