ANOMALOUS HALL EFFECT IN WEAK PINNING HIGH-Tc SUPERCONDUCTORS

Taking into account both pinning and thermal fluctuation and employing the single flux flow model of Wang, Dong, and Ting (WDT), we have performed numerical study to investigate the flux motion in the weak pinning environment in the mixed-state of high-Tc superconductors. We find that there exist two kinds of weak pinning regime, one possesses low pinning concentration but strong individual pinning potentials, the other consists of high pinning concentration but weak individual pinning potentials for the double sign reversal of Hall resistivity ρxy. Moreover, our simulation and analysis suggest that the weak collective pinning effect may not be a good reason for the abnormal Hall effect. These results are well consistent with recent measurement of Bi2Sr2CaCu2O8 (BSCCO), Tl2Ba2CaCu2O8 (TBCCO) and HgBa2CaCu2O6 (HBCCO) and collective pinning theories for Hall effect.