Role of reduction process in the transport properties of electron-doped oxide superconductors

Physica C 243, 319 (1995)

Electron-doped oxides such as Nd_(2-x)Ce_xCuO_4 become metallic and superconducting only after annealing in a reducing atmosphere. Here we propose an explanation for this fact and discuss its implications for the understanding of the nature of the charge carriers in these materials as well as in hole-doped oxide superconductors.