Experimental test of the T2 law for the Hall angle from Tc to 500 K in oxygen-reduced YBa2Cu3O6+x crystals

In both ''90-K'' and ''60-K'' YBa2Cu3O6+x crystals, we find that the T2 law for the Hall angle, measured with field Hc, remains valid for temperatures T between Tc and 500 K. The persistence of power-law behavior over this wide range is not affected by oxygen reduction. In contrast to this anomalous behavior, the Hall coefficient observed with Hc is negative and temperature independent. Measurements of the in-plane resistivity ρxx to 500 K disclose the existence of a kink temperature TK (∼320 K) that separates a high-temperature power-law regime from a low-temperature region in which ρxx displays significant curvature.