Title :
Fabrication and measurement of intrinsic Josephson junctions in misaligned films of Tl2Ba2CaCu2O8
Author :
Chana, O.S. ; Kuzhakhmetov, A.R. ; Hyland, D.M.C. ; Eastell, C.J. ; Dew-Hughes, D. ; Grovenor, C.R.M. ; Koval, Y. ; Mößle, M. ; Kleiner, R. ; Muller, P. ; Warburton, P.A.
Author_Institution :
Dept. of Electron. Eng., King´´s Coll., London, UK
fDate :
3/1/2001 12:00:00 AM
Abstract :
Intrinsic Josephson bridges have been patterned in films of Tl2Ba2CaCu2O8. Due to our device geometry we have used films that are misaligned at 20° to the substrate surface. This misalignment has been confirmed using four-circle x-ray diffraction and cross-sectional transmission electron microscopy. Our films still retain a high critical temperature (108 K) despite their misalignment. The resistive anisotropy of the film is comparable to single crystal data. The product of the critical current and normal state resistance is equal to 14 mV at 4.2 K and is independent of the critical current density. These two achievements are attributed to the-lack of engineered interfaces in our intrinsic junctions. A run-to-run variation in the critical current is explained by the presence of non-Josephson shunts in the junction. Junctions with fewer non-Josephson shunts show greater hysteresis
Keywords :
Josephson effect; barium compounds; calcium compounds; critical current density (superconductivity); high-temperature superconductors; superconducting thin films; superconducting transition temperature; thallium compounds; transmission electron microscopy; Tl2Ba2CaCu2O8; critical current; critical current density; cross-sectional transmission electron microscopy; device geometry; four-circle x-ray diffraction; high critical temperature; high temperature superconductor; intrinsic Josephson junctions; misaligned films; misalignment; non-Josephson shunts; normal state resistance; resistive anisotropy; Bridges; Critical current; Fabrication; Geometry; Josephson junctions; Substrates; Surface resistance; Temperature; Transmission electron microscopy; X-ray diffraction;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
