MAGNETORESISTANCE FOR SINGLE-CRYSTALS OF BI2SR2CACU2OX IN PULSED HIGHMAGNETIC-FIELDS UP TO 40-T

The magnetoresistance along the c-axis of a single crystal of Bi2Sr2Ca Cu2Ox (Bi(2212)) was measured in pulsed high magnetic fields up to 40 T. The resistance increased steeply from zero with the application of a magnetic field below T(c)(B = 0), and became larger than the value j ust above T(c), as was reported previously. In the high field region, however, decrease of the resistance was observed. It is shown that thi s experimental fact, a kind of negative magnetoresistance in the high field region, can be explained by the contribution of the density of s tates term to the fluctuation conductivity.