Anomalous Hall Effect In Fenipt Ternary Ordered Alloy Films

With the development of spintronics materials,the demands of miniaturization and versatility for electronic devices are getting higher.Anomalous Hall Effect(AHE)is one of the main effects in spintronics and an important method to characterize the magnetic properties of ferromagnetic materials.It has been widely studied by scholars.Most studies of anomalous Hall effect focus on three kinds of scattering mechanisms,such as intrinsic contribution,skew scattering and side-jump scattering.Theoretical studies have shown that the anomalous Hall effect is closely related to the Fermi level of the element.In addition,some studies have pointed out that the contribution of impurity scattering in anomalous Hall effect strongly depends on physical factors such as the degree of chemical long range ordering and film thickness.Based on the above,the research of this thesis contains the following two directions:1.L10(FexNi1-x)0.5Pt0.5(0?x?1)ternary ordered alloy films with different compositions are selected to study the effect of Fermi level on AHE.A series of L10 FexNi1-xPt ternary ordered alloy films with a thickness of 15±3 nm are prepared by DC magnetron sputtering.All samples are of fct structure.We use ?xy=a'?xx0=a"?xxT+b?xx2 to analyze the mechanisx of the anomalous Hall effect the changing of the Fermi level when the Ni atoms are replaced by Fe atoms.The sign change of the sum of the Berry curvatures on the Fermi surface,which results in the sign change of the intrinsic mechanism.It can be seen that the intrinsic mechanism play dominate role in L10 FexNi1-xPt.2.(Fe0.6Ni0.4)0.5Pt0.5(FeNiPt)ternary alloy films with different degrees of chemical long range ordering are selected to study the influence of the chemical ordering on the impurity scattering and intrinsic scattering mechanism in the anomalous Hall effect.The FeNiPt ternary alloy films with a thickness of 15±3 nm are prepared by DC magnetron sputtering with different annealing temperatures.As the annealing temperature increases,the microstructure of the sample gradually changes from fcc structure to fct structure.Meanwhile,the degree of ordering increases.We use ?xy=a'?xx0+a"?xxT+b?xx2 to analyze the mechanism of the anomalous Hall effect.We find that the skew scattering contribution is reduced.The side-jump scattering contribution is decreases and the intrinsic contribution is increases.The intrinsic contribution in the Anomalous Hall effect of high order films is mainly due to the enhancement of the spin-orbit coupling energy of the system.