Measurement technique of magnetic anisotropy field on patterned magnetic structures

We propose an electric measurement technique for the magnetic anisotropy field of ferromagnetic thin films and their tiny patterned structures, particularly, in the case of in-plane magnetic anisotropy. This technique measures the anomalous Hall resistance by sweeping the angle or strength of the external magnetic field. The magnetic anisotropy field can be determined explicitly from the linear dependence of the Hall resistance on the angle and strength of the external magnetic field. The present technique can be applied to both ferromagnetic thin films and their patterned magnetic structures with small volumes, overcoming the signal resolution limit of conventional techniques.