Title :
Step-edge and stacked-heterostructure high-T/sub c/ Josephson junctions for voltage-standard arrays
Author :
Benz, S.P. ; Reintsema, C.D. ; Ono, R.H. ; Eckstein, J.N. ; Bozovic, I. ; Virshup, G.F.
Author_Institution :
Nat. Inst. of Stand. & Technol., Boulder, CO, USA
fDate :
6/1/1995 12:00:00 AM
Abstract :
We have explored two high-transition-temperature Josephson junction technologies for application in voltage standard arrays: step-edge junctions made with YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// and Au normal-metal bridges, and stacked series arrays of Josephson junctions in selectively doped, epitaxially grown Bi/sub 2/Sr/sub 2/CaCu/sub 2/O/sub 8/ heterostructures. For both kinds of junctions, Shapiro steps induced by a microwave bias were characterized as a function of power. We compare the technologies with respect to critical current and normal resistance uniformity, maximum achievable critical current, critical-current normal-resistance product, and operating temperature.<>
Keywords :
Josephson effect; barium compounds; bismuth compounds; critical current density (superconductivity); high-temperature superconductors; measurement standards; strontium compounds; superconducting microbridges; superconducting microwave devices; yttrium compounds; Bi/sub 2/Sr/sub 2/CaCu/sub 2/O/sub 8/; Shapiro steps; YBa/sub 2/Cu/sub 3/O/sub 7/; maximum achievable critical current; microwave bias; normal resistance uniformity; normal-metal bridges; operating temperature; stacked series arrays; stacked-heterostructure high-T/sub c/ Josephson junctions; step-edge junctions; voltage-standard arrays; Artificial intelligence; Capacitance; Critical current; Frequency; Gold; Josephson junctions; NIST; Superconducting devices; Temperature; Voltage;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
