THE DC-CURRENT DESTRUCTION OF SUPERCONDUCTING STATE AND HYSTERESIS EFFECTS IN BA-K-BI-O

The dc-current destruction of superconducting state in Ba-K-Bi-O was r egistered simultaneously both by measuring V-I characteristic and magn etic susceptibility chi. The experiments were carried out on the polyc rystall samples in the temperature interval 1.5-4.2 K. The hysteresis of both characteristics was observed, the temperature dependencies of hysteresis value of V-I and c-I being quiet opposite. The nonmonotonic temperature dependence of I has been found. The observed effects can be explained in the framework of the model, according to which the spe cial nonhomogeneous state can arise - the space structure of the alter nate superconducting and insulating regions with Josephson tunnelling between the former.