Title :
Fabrication of heteroepitaxial Bi/sub 2/(Sr,Ca)/sub 3/Cu/sub 2/O/sub x//Bi/sub 2/Sr/sub 2/CuO/sub y//Bi/sub 2/(Sr,Ca)/sub 3/Cu/sub 2/O/sub x/ Josephson junctions
Author :
Satoh, T. ; Fujita, J. ; Yoshitake, T. ; Tsuge, H.
Author_Institution :
NEC Corp., Tsukuba, Japan
fDate :
3/1/1993 12:00:00 AM
Abstract :
Josephson junctions using c-axis oriented heteroepitaxial Bi/sub 2/(Sr,Ca)/sub 3/Cu/sub 2/O/sub x//Bi/sub 2/Sr/sub 2/CuO/sub y//Bi/sub 2/(Sr,Ca)/sub 3/Cu/sub 2/O/sub x/ trilayer films have been fabricated. The junctions showed the resistively shunted junction-like characteristic up to 50 K. The highest value of the product of the critical current and the normal state resistance of the junctions was about 0.2 mV. Clear Shapiro steps at the expected voltages were observed up to 50 K in the presence of external microwave irradiation. The microwave power dependence of the height of these steps was qualitatively in agreement with the resistively shunted junction model behavior. Moreover, the Fraunhofer-like diffraction pattern in an applied magnetic field was clearly observed. These results indicate that nearly uniform Josephson junctions had been fabricated.<>
Keywords :
Josephson effect; bismuth compounds; calcium compounds; high-temperature superconductors; photolithography; sputter deposition; sputter etching; strontium compounds; superconducting epitaxial layers; superconducting junction devices; vapour phase epitaxial growth; 2212/2201/2212 junctions; Bi/sub 2/(Sr-Ca)/sub 3/Cu/sub 2/O/sub x/-Bi/sub 2/Sr/sub 2/CuO/sub y/-Bi/sub 2/(Sr-Ca)/sub 3/Cu/sub 2/O/sub x/; Fraunhofer-like diffraction pattern; HTSC; Josephson junctions; Shapiro steps; applied magnetic field; c-axis oriented heteroepitaxial; critical current-resistance product; external microwave irradiation; ion milling; photolithography; resistively shunted junction-like characteristic; sputter deposition; Bismuth; Electromagnetic heating; Fabrication; Josephson effect; Leakage current; Magnetic fields; Magnetic hysteresis; Strontium; Temperature dependence; Voltage;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
