Superconducting properties of Ce-substituted TaSr2(Gd,Ce)2Cu2Oy

A layered cuprate TaSr2Gd1+xCe1−xCu2Oy for x = 0.4–0.8 has been successfully synthesized by solid state reaction. X-ray powder diffraction analysis indicates that nearly all the peaks from the samples can be indexed to a single phase of Ta-1222. The sample with nominal composition TaSr2Gd1.6Ce0.4Cu2Oy showed a tetragonal structure with lattice parameters a = 3.858A° , c = 28.81A° with space group most likely I4/mmm. The TaSr2Gd1+xCe1−yCu2Oy compound exhibits a narrow superconducting region near x = 0.6 with Tc−onset = 30 and Tc−zero=10 K as determined by d.c. electrical resistance versus temperature measurements. C 2006 Springer Science + Business Media, Inc.