Influence of the character of filling the electron shells of central atoms in the structure of granular high-temperature superconductors of 1:2:3 type on phase transitions

In this paper, fundamental studies of the influence of the nature of filling the electron shells of the central atoms in the crystal lattice of granular high-temperature superconductors RеBa2Cu3O7–δ (where Re = Y, Dy) on the electrophysical properties of two-level HTSCs are carried out for the first time. We focused our attention on the kinetics of phase transitions occurring in both subsystems of these two model objects of granular HTSCs under the action of an external magnetic field and transport current with a change in temperature. It is shown that the presence of magnetoactive atoms in the crystal structure of granular HTSCs leads to a significant decrease in the critical temperature of the phase transition Tc2J = Tρ=0, i.e., the temperature of the occurrence of resistivity in the “weak links” subsystem when an external magnetic field is applied to a high-temperature superconductor. That is, the presence of magnetoactive atoms in the crystal structure of granular HTSCs has the most significant effect on dissipative processes in the “weak links” subsystem.