Title :
Investigation for the basic characteristics of HTS SFQ logic gate
Author :
Saitoh, K. ; Utagawa, T. ; Enomoto, Y.
Author_Institution :
Supercond. Res. Lab., Int. Supercond. Technol. Center, Tokyo, Japan
fDate :
6/1/1999 12:00:00 AM
Abstract :
The characteristics of a simple logic gate which consists of an rf-Superconducting QUantum Interference Device (SQUID) and dc-SQUID has been investigated in connection with the Single-Flux-Quantum (SFQ) logic operation and Josephson junction characteristics. The Josephson junctions were made of Neodymium Barium Copper Oxide thin film employing Focused Ion Beam technology. We confirmed the generating SFQ in the rf-SQUID and simultaneous read-out by the dc-SQUID up to 50 K. It has been found that the temperature dependence of output voltage level decreased more rapid than that of critical current normal resistance product. The origin of the discrepancy was studied using a phenomenological model of the Josephson junction and numerical simulation.
Keywords :
Josephson effect; SQUIDs; barium compounds; focused ion beam technology; high-temperature superconductors; neodymium compounds; superconducting logic circuits; superconducting thin films; 50 K; DC SQUID; HTS thin film; Josephson junction; NdBaCuO; RF SQUID; SFQ logic gate; critical current normal resistance product; current-voltage characteristics; focused ion beam technology; numerical simulation; phenomenological model; simultaneous readout; temperature dependence; Barium; Copper; High temperature superconductors; Interference; Josephson junctions; Logic devices; Logic gates; Neodymium; SQUIDs; Transistors;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
