Magnetoresistance of HTSC ceramics at different doping levels

摘要

The magnetoresistance of the superconducting YBa_2Cu_3O_x-ceramics in the normal state with the oxygen content varied by annealing was studied. It has been established, that annealing has resulted not only in increasing the critical temperature, but also decreasing of the normal state resistivity and changing it behavior. Under action of magnetic field the character of resistivity of the initial and annealed samples changed in different ways. For describing such properties of cuprate superconductors the model of electronic phase separation is used.