HALL-EFFECT AND FLUX DYNAMICS IN YBA2CU3O7/PRBA2CU3O7 MULTILAYERS IN THE MIXED-STATE

We report on the temperature and magnetic-field dependence of both the longitudinal resistivity rho(xx) and Hall resistivity rho(xy) of a [YBa2Cu3O7(72 Angstrom)/PrBa2Cu3O7(12 Angstrom)](25) multilayer in the mixed state. Near T-c, the Hall resistivity rho(xy) undergoes a sign reversal in the low-field region, while at the temperature where rho(xy) shows a minimum, the vortices have the highest mobility An analysis of the Hall conductivity sigma(xy) reveals that sigma(xy) can be successfully described by the two terms which are related to the quasiparticle excitations and the motion of free vortices, respectively. The high-T-c multilayers also demonstrate the Hall sign reversal and scaling behavior rho(xy)(proportional to)rho(xx)(2), previously reported for as-grown high-T-c compounds.