superconductivity of Bi2-x Nax Pb0.3 Sr2Ca2Cu3O10+δ for 0 ≤ x ≤ 0.5 System


High- temperature oxide superconductivity of Bi-Sr-Ca-Cu-O system and Tl-Ba-Ca-Cu-O system without any rare- earth elements were discovered by Maeda et al (1) and Hermann (2),respectively. Maeda and co-workers observed a superconducting onset temperature of about 120K,which was higher than that of Ba2YCu3O7 by more than 10K.Takano et al.