Title :
Electrical properties of YBa/sub 2/Cu/sub 3/O/sub 7-x//PrBa/sub 2/Cu/sub 3/O/sub 7-x/ bi-layers
Author :
Terai, H. ; Sanada, S. ; Fujimaki, A. ; Takai, Y. ; Hayakawa, H.
Author_Institution :
Dept. of Electron., Nagoya Univ., Japan
fDate :
3/1/1993 12:00:00 AM
Abstract :
The authors, investigated the electrical properties of YBa/sub 2/Cu/sub 3/O/sub 7-x/(YBCO)/PrBa/sub 2/Cu/sub 3/O/sub 7-x/(PBCO) bi-layers by fabricating YBCO/PBCO/Au/Nb junctions. For 5-nm-, 10-nm- and 20-nm-thick PBCO, supercurrents could be observed and uniformly distributed in the junction. The normal coherence length xi /sub n/ of PBCO was estimated to be 4 nm at 4.2 K from the relationship between I/sub c/R product and PBCO thickness. However, the junction resistance R was extremely small, compared with that of bulk PBCO for thicker PBCO. The temperature dependence of R posed the problem that a long-range interaction at least up to 300 nm existed between YBCO and PBCO below the critical temperature of YBCO in spite of the short coherence length xi /sub n/ of PBCO.<>
Keywords :
barium compounds; coherence length; high-temperature superconductors; praseodymium compounds; superconductive tunnelling; yttrium compounds; 5 to 20 nm; YBCO/PBCO/Au/Nb junctions; YBa/sub 2/Cu/sub 3/O/sub 7-x/-PrBa/sub 2/Cu/sub 3/O/sub 7-x/; bi-layers; coherence length; electrical properties; high temperature superconductor; junction resistance; supercurrents; temperature dependence; uniformly distributed; Couplings; Critical current; Critical current density; Current density; Gold; Magnetic fields; Niobium; Probes; Thickness measurement; Yttrium barium copper oxide;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
