Electron tunneling for YBa2Cu3O7-x(YBCO) thin film prepared by activated reactive evapo-ration technique has been studied using normal conductor-insulator-superconductor (NIS) tunnel junctions and using superconductor-insulator-superconductor(SIS) tunnel junctions. Based on data of NIS using single crystal thin film of YBC0(001), reproducible gap parameter ▵⊥(4.6K) of 9.0 ± 1.8meV and a coupling constant of 2.4 ± 0.5 < 2▵⊥(0)/kTc < 3.5 ±0.7 in perpendicular direction to the Cu-0 planes were obtained. The quasi-particle density of states exhibits a lifetime broadening picture. The recombination lifetime t r of quasiparticle decreases as the temperature approaching to the transition point from low temperatures. 77, at 60K is estimated to be 10-13 s. Multipeaks which are often observed in differential tunnel conductance spectra of (110) or (103) oriented thin film of YBCO are understood as not to be an intrinsic property of YBCO.

Date Published: 19 March 1990
PDF: 11 pages
Proc. SPIE 1187, Processing of Films for High Tc Superconducting Electronics, (19 March 1990); doi: 10.1117/12.965173

Published in SPIE Proceedings Vol. 1187:
Processing of Films for High Tc Superconducting Electronics
T. Venkatesan, Editor(s)