Title :
Single and stacked Josephson junctions based on c-axis YBCO/PBCO multilayers
Author :
Bari, M.A. ; Ghyselen, B. ; Tarte, E.J. ; Somekh, R.E. ; Yan, Y. ; Evetts, J.E. ; Blamire, M.G. ; Chew, N.G. ; Humphreys, R.G.
Author_Institution :
Dept. of Mater. Sci. & IRC, Cambridge Univ., UK
fDate :
6/1/1995 12:00:00 AM
Abstract :
Using whole wafer superconducting device technology we have fabricated vertically stacked sandwich junctions with c-axis oriented YBCO/PBCO/YBCO trilayers and double barrier junctions. The resulting devices exhibit supercurrents through 130 nm at 4.2 K. We have observed RSJ-like I-V curves, Shapiro steps and almost Fraunhofer-like dependence of the critical current as a function of magnetic field. The scaling behaviour of devices fabricated on perovskite (SrTiO/sub 3/ and LaAlO/sub 3/) and MgO substrates differ. The results indicate a certain uniformity for the barriers on the scale of the size of the junction. We propose different mechanisms for supercurrent and quasiparticle transport through the PBCO barrier for the two substrate types.<>
Keywords :
Josephson effect; barium compounds; critical currents; high-temperature superconductors; praseodymium compounds; superconducting device testing; superconducting junction devices; yttrium compounds; 4.2 K; Fraunhofer-like dependence; Josephson junctions; LaAlO/sub 3/; MgO; RSJ-like I-V curves; Shapiro steps; SrTiO/sub 3/; YBCO/PBCO/YBCO trilayers; YBa/sub 2/Cu/sub 3/O/sub 7/-PrBa/sub 2/Cu/sub 3/O/sub 7/-YBa/sub 2/Cu/sub 3/O/sub 7/; c-axis YBCO/PBCO multilayers; critical current; double barrier junctions; quasiparticle transport; scaling behaviour; supercurrents; vertically stacked sandwich junctions; whole wafer superconducting device technology; Critical current; Fabrication; Gold; Josephson junctions; Magnetic fields; Magnetic materials; Nonhomogeneous media; Superconducting devices; Superconductivity; Yttrium barium copper oxide;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
