Thomas E. Karis, C. Mark Seymour, et al.
Rheologica Acta
Tunnel junctions with good quasiparticle (Giaever) and pair (Josephson) tunneling characteristics have been made on electron-beam coevaporated thin films of some important high-temperature superconductors which have the A-15 crystalline structure. Using the thermally grown oxide of niobium tin to make Nb-SnoxidePb junctions we estimate the gap, Nb-Sn, as a function of composition from the current-voltage characteristics. Stoichiometric Nb3Sn is strong coupling with 2kBTc=4.2-4.4 whereas with less tin Nb-Sn has a low Tc and becomes weak coupling. On vanadium silicon we could only make good junctions by evaporating a thin silicon layer, with thickness in the range 1.6-16 nm, on the fresh A-15 film before junction fabrication. V-Si is essentially weak coupling for all compositions with 2kBTc=3.50.2. The characteristics of tunnel junctions on high-Tc niobium-germanium films always show evidence for multiple gaps and the data on this interesting material are more difficult to interpret. © 1979 The American Physical Society.
Thomas E. Karis, C. Mark Seymour, et al.
Rheologica Acta
T.N. Morgan
Semiconductor Science and Technology
Kenneth R. Carter, Robert D. Miller, et al.
Macromolecules
Mitsuru Ueda, Hideharu Mori, et al.
Journal of Polymer Science Part A: Polymer Chemistry