The Planar Hall Effect Of Thin Films With In-Plane Uniaxial Magnetic Anisotropy

Recently,the electronic transport properties of magnetic films have received much attention.The planar Hall effect originates from the spin-orbit coupling,which is the transverse effect of magnetoresistance,have widely application in spintronic devices including magnetic senor,magnetic random access memories and logic device.The planar Hall effect is extremely sensitive to the direction of magnetic moment,which make it a suitable tool to investigated magnetism phenomenon such as magnetic domain pinning,magnetization reversal and magnetic anisotropy.Therefore,the study of planar Hall effect is a significant for both industrial application and academic value.In this paper,the Fe80Ni20-O monolayer films were deposited by magnetron sputtering.We systematically investigate the surface morphology,microstructure,static magnetism and electronic transport properties of thin films.The method of controlling the magnetic anisotropy of Fe80Ni20-O thin films was discussed.The planar Hall effect and the magnetization reversals process of the film were measured.The main research contents of this paper are as follows:In this letter,we prepared a series of Fe80Ni20-O thin films with different thickness and different oblique sputtering angle by using oblique sputtering method.The monolayer films with in-plane uniaxial magnetic anisotropy was fabricated by rotates substrate without inducing magnetic field,and magnetic anisotropy in 0?100 Oe range.With the increase of the thickness of Fe80Ni20-O thin films,the in-plane uniaxial magnetic anisotropy of the film increases gradually,and the coercivity of thin films decreases first and then decreases.With the increase of the oblique sputtering angle,both the magnetic anisotropy and the coercivity of Fe80Ni20-O thin films are increasing gradually.The influence of external magnetic field and applying current on the planar Hall effect of Fe80Ni20-O monolayer films were studied.Both the angle-dependent planarHall resistance curve and the field-dependent planar Hall resistance curve reveals that the direction of magnetization of films was determined by the competition between magnetic anisotropy and external magnetic field.The results of planar Hall resistance curve of Fe80Ni20-O monolayer films with different applying current showed that the magnitude of current has no impact on the planar Hall effect.Moreover,the planar Hall resistance can be express as ?PHE=1/2??sin2(?+a).Here,the angle a between the easy axis of magnetization and the applying current.It reveals that the direction of current has no effect on the planar Hall effect in essence.Based on the Stoner-Wohlfarth(SW)model and the rotational magnetization curve method,a new routine was proposed to described the magnetization reversal of Fe80Ni20-O films with in-plane uniaxial magnetic anisotropy.At the same time,we prepared a Fe80Ni20-O monolayer film with a thickness of 60 nm,the result of experiment are in excellent agreed with the theory The direction of magnetization is mainly influenced by uniaxial magnetic anisotropy in low external magnetic field.The process of magnetization reveals likely to is the domain wall displacement when the magnitudes of applying field are close to the magnetic anisotropy.The direction of magnetization is mainly influenced by the external magnetic field under high external magnetic field.