Effects of oxygen deficiency on the superconductivity in Nd2-xCexCuO4-δ have been systematically investigated. The value of Tc strongly depends on x and δ. Over-reduction is found to decrease Tc because of randomness and/or over-doping of carriers. Effects of partial substitution of Ni, Zn and Ga for Cu have been also studied. The Ni substitution markedly decreases Tc , while the Ga substitution does not. This is discussed relating to the antiferromagnetic phase transition in samples with smaller x.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering