We have measured electrical resistivity and AC susceptibility of Bi2Sr2CaCu2O8+δ with 0.20 ≦ δ ≦ 0.34, annealed under high oxygen pressure. With increasing δ, the superconducting transition temperature Tc decreases for 0.20 ≦ δ ≦ 0.27 and is almost constant, ∼45K, for 0.27 ≦ δ ≦ 0.34. The δ dependence of Tc may be related to those of the average valences of both Cu and Bi ions.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering