PHASE-DIAGRAM FOR THE ELECTRON-DOPED ND2-XCEXCUOY SUPERCONDUCTING SYSTEM

We report a refined phase diagram for the electron-doped Nd2-xCexCuOy superconducting system in the range 0.120 less-than-or-equal-to x less -than-or-equal-to 0.190 with DELTAx=0.005. It is found that the highes t T(c)(rho=0) approximately 17 K is confined to the very narrow range 0.145 less-than-or-equal-to x less-than-or-equal-to 0.150; a T(c onset ) approximately 24 K with sharp superconducting transition is also obs erved. An attempt is made to understand the T(c) dependence on the var iation of the oxygen content (y) in the Nd2-xCexCuOy system.