ELECTRICAL AND MAGNETIC-PROPERTIES OF THE METALLIC ND1.85CE0.15CUO4-Y SUPERCONDUCTOR

Samples of Nd2-xCexCuO4-y with x = 0.13, 0.15 and 0.17 have been prepared under N2 and He atmospheres at various temperatures. AC electrical resistance R(T) measurements reveals a metallic behavior in the normal state resistance for the ND1.85Ce0.15CuO4-y sample which was annealed in the He atmosphere at 1000-degrees-C. A superconducting transition occurs at 24 K with the mid-point transition temperature T(c)(50%) = 19 K and a superconducting transition width DELTA-T(c) (T(c)(90%)-T(c)(10%)) = 9 K. DC magnetization measurement reveals bulk superconductivity in the sample. Powder X-ray diffraction patterns indicate a single-phase Nd2CuO4-y structure in this sample. The lattice parameters deduced from the diffraction peaks yield the values of a = 3.950 +/- 0.002 angstrom and c = 12.067 +/- 0.009 angstrom, respectively.