Effect of Composition and Atomic Substitutions on Structure and Superconductivity of Y1Ba2Cu3Ox

In the present work, ceramic samples of Y-Ba-Cu-O of a varied composition were synthesized in order to identify a superconducting phase and to construct the phase diagram of the system. From the viewpoint of elucidating the nature of high temperature superconductivity, an important role is given to experiments studying the influence of the substitution for elements in different lattice sites of high temperature superconductors on crystal structure, electric and magnetic properties. The replacement of atoms in the starting compound Y1Ba2Cu30x by the atoms of elements differing in mass, size, charge and spin may reveal the role of different mechanisms responsible for high temperature superconductivity. In the present work, the influence of the total and partial atomic substitutions of rare-earth elements Dy, Ho, Er, Pr, etc. for Y, and Sr, Fe for Ba and Cu, respectively, has been investigated.