High temperature performance of HTS step-edge DC SQUIDs

YBa/sub 2/Cu/sub 3/O/sub 7/ (YBCO) step edge DC superconducting quantum interference devices (SQUIDs) have been developed which exhibit characteristics suitable for near-term incorporation into high-temperature superconductive (HTS) circuitry. Step-edge junction DC SQUIDs for series array interferometer logic (SAIL) digital applications exhibit resistively shunted junction (RSJ) properties, 65 K I/sub c/ values of approximately 150 mu A, 65 K I/sub c/R/sub n/ values up to approximately 300 mu V, and large I/sub c/ modulation (>50%) in accordance with a standard DC SQUID model. 65 K SQUID switching voltages of approximately 100 mu V have been demonstrated and are sufficient for near-term applications of SAIL digital circuitry operating on a cryocooler platform. >