A. Odagawa et Y. Enomoto, NORMAL RESISTIVITY AND SUPERCONDUCTIVE PROPERTIES ON YBA2(CU1-XNIX)(3)O-7-DELTA FILMS, Physica. C, Superconductivity, 248(1-2), 1995, pp. 162-166
We report the successful fabrication and characterization of YBa2(Cu,N
i)(3)O-7-delta epitaxial thin films. On doping with Ni, T-c decreases
and resistivity increases for YBa2(Cu1-xNix)(3)O-7-delta films. The re
duction rate of T-c, dT(c)/dx, changes at x similar to 3% from similar
to -5.4K/% for low Ni concentrations to -2.1K/% for higher concentrat
ions. The rate of increase of resistivity, d rho(n)/dx, also changes a
t the same doping content. This dependence of T-c and resistivity sugg
ests a site preference change of the Ni atoms, from the CuO2 plane to
the CuO chain.