DOUBLE-MICROBRIDGE DC SQUIDS MADE FROM YBCO SUPERCONDUCTING FILMS

Abstract

Double-microbridge DC SQUIDs have been fabricated from YBCO superconducting films by lithographically patterning technique. The voltage versus the applied magnetic field dependence of a DC SQUID has been obtained in the region of temperature from 4.2 K to 23 K, The largest output voltage of the devices used in our experiments is 3.4 uV /Φ 0 (Φ 0 is h/2e the flux quantum). The smallest measured periodicity of the flux-voltage characteristics of the DC SQUID, 12.7 mG, is consistent with the designed value. In addition, some properties of the flux-voltage characteristics of the DC SQUIDs have been discussed.