Superconductive copper-containing oxide materials of the formula ApBqCu2O4+/-r

摘要

A superconductive oxide material having an infinite layer structure and having the following formula: ApBqCu2O4+/-r wherein A and B are different and each represent an element selected from lanthanoid elements and elements belonging to Groups IA, IIA and IIIA of the Periodic Table, p is between 0.9 and 1.1, q is between 0.9 and 1.1 and r is between 0 and 0.6. The oxide material has a crystal structure belonging to a tetragonal system of P4/mmm and 1-123 having the following lattice parameters: 3.8 ANGSTROM