VOLTAGE-CURRENT CHARACTERISTIC BETWEEN 10(-13) V/CM AND 10(-3) V/CM OF BSCCO AND TIME DECAY OF THE MAGNETIZATION

Using a novel inductive method we have measured the voltage-current characteristic in rings of melt processed Bi-2212 ceramics between 10(-13) V/cm and 10(-3) V/cm. The measurements were performed above 64 K in magnetic fields below 1000 Oe. The voltage-current characteristic obeys the relation E = E(o)(j/j(o))alpha over the whole investigated region. In zero applied field, time decay measurements of the magnetization M were performed on these ceramic samples and on single crystals. Both materials clearly revealed a nonlogarithmic decay when the decrease of M(t) could be observed to less than about 70 % of its initial value.