Hall anomaly in the mixed state of overdoped Y1−xCaxBa2Cu3O7−δ thin film

The longitudinal ρxx and Hall resistivity ρxy of Y0.8Ca0.2Ba2Cu3O7−δ thin film were measured in different magnetic fields up to 10.0 T. The anomalous sign reversal and a second sign reversal were observed in the overdoped sample. A scaling law, ρxy∝ρxxβ with β = 1.7 ± 0.1, was determined for the field above 1 T. The experimental results indicate that the first sign reversal and the scaling law may have no close connection with each other.