  The electrical resistivity of polycrystalline Bi2Sr2Ca2Cu3O10-x (Bi-2223) was
measured vs. applied magnetic fields up to 0.45 T, applied currents up to 1 A,
and temperature from liquid nitrogen temperature (LN2) to room temperature. In
the lowest temperature region, the only truly zero resistivity was observed
when the magnetic field was zero; otherwise, a quadratic dependence on the
magnetic field occurred. Hysteresis was noted at the higher currents. Current
vs. voltage curves in this region revealed a non-ohmic resistivity. In the
transition region to the mixed state, indications of negative resistivity and
suggestions of a phase change were observed. Arrhenius plots yielded activation
energies of around 0.05 eV/molecule. In the mixed state region up to the
transition temperature of ~110K, analysis implied that 4 superconducting
quantum states exist and that they are cooperatively filled by the
superconducting charge carriers. The occupation of the superconducting quantum
states is negatively affected by the applied magnetic field and by the applied
current. No effect on the polarity or direction of the magnetic field with
respect to the direction of the current was observed.
