Superconductivity up to 110 K in Bi2Sr2Ca2Cu3O10 compounds

2014 In the Bi-Sr-Ca-Cu-O system, we have studied the compound with the ideal formula Bi2Sr2Ca2Cu3O10, responsible for the superconductivity up to 110 K. The magnetic measurements reveal the presence of two phases in the samples with superconducting transitions up to 80 K and 110 K. By varying the composition and the thermal treatment of those samples, we have succeeded in increasing the amount of the superconducting phase with Tc up to 110 K. The Meissner effect reaches 30 % of 3/8 03C0 at 90 K for the undoped samples and more than 50 % for the samples doped with Pb. Because of the high reversibility of the magnetization versus magnetic field around Tc, we have evaluated the critical thermodynamic field. This one gives an electronic specific heat coefficient similar to the one of YBaCuO compounds. Revue Phys. Appl. 24 (1989) 485-488 MAI 1989, Classification Physics Abstracts 74.70