New Resistance Anomaly in Superconducting Bi₂Sr₂CaCu₂O₈ Single Crystals

We have measured the resistance of some Bi₂Sr₂CaCu₂O₈ superconducting single crystals along ab plane and the c axis. For some of the single crystals, a resistivity anomaly near the superconducting transition temperature is observed in the ab plane. This giant resistance peak is independent of the small driving current (I ≤40 mA), and the peak is suppressed and vanished gradually with the increasing applied magnetic field (> 100 G). We proposed that the resistance peak is a quasi-reentrant behavior due to the superconducting phase inhomogeneous distribution.