Tuning anomalous Hall conductivity in L1 FePt films by long range chemical ordering

For L10 FePt films, the anomalous Hall conductivity σxy=−aσxx−b, where a=a0f(T), b=b0f(T), and f(T) is the temperature dependence factor of the spontaneous magnetization. With increasing chemical long range ordering S, a0 changes its sign accompanied by a reduction of its magnitude and b0 increases monotonically. The spin-orbit coupling strength is suggested to increase with increasing S. As an approach, the long range chemical ordering can be used to control the anomalous Hall effect in ferromagnetic alloy films.