A Scaling Behavior of Anomalous Hall Effect in Cobalt Doped TiO2

Anomalous Hall effect (AHE) is a generally observed phenomenon in ferromagnetic metals representing spin polarized nature of itinerant carriers. However, the microscopic mechanism has not been clarified for long debates. Recent advances in the theory are to unveil the mechanism. Here, we present an AHE in a room temperature ferromagnetic semiconductor cobalt doped TiO2. This compound shows a scaling behavior of the AHE: the anomalous Hall conductivity σAH approximately follows the relation σAH ∞ σxx 1.6 (σxx, conductivity) over five decades of σxx, irrespective of the electronic state, i.e., metallic or insulating conduction.