Theoretical Studies On The Magnetic Anisotropy Of Multilayer Metal Films

For the information age,information storage has become an important issue.In order to improve information storage and improve the information storage density of magnetic recording media,it is a common practicable method.For magnetic recording medium,a superparamagnetic phenomenon occurs when a storage unit is reduced to the nanoscale.Therefore,the material needs a larger magnetic anisotropy to resist the magnetic spin flip caused by the thermal disturbance.Based on the first principles calculation system,we have studied the magnetic anisotropy of Fe-Ir multilayer system on Fe substrate.In the Fe-Ir system,when the Ir atoms are located in the outermost layer and have larger spin magnetic moments,the system has larger magnetic anisotropy properties.Our further study shows that the response of the magnetic anisotropy to the electric field is significantly higher than that o f the antiferromagnetic field when the system is in the ferromagnetic case.However,when the Fe atom is located at the outermost layer,the system has very small magnetic anisotropy,but the easy axis of magnetization will point in the direction of the steering surface with the increase of the electric field.When the Fe atom is adsorbed on the halogen atom in the outer Fe-Ir system,the magnetic anisotropy can be greatly improved,and the direction of the easy magnetization axis turns with the different adsorbate atoms from the surface to the surface.After adsorption,the system will change from antiferromagnetic to ferromagnetic state,and its response to electric field will be greatly improved compared with that before adsorption.After the adsorption of the adsorbed halogen atoms to the first host atom,the magnetic anisotropy of the system has been greatly improved compared with that before the adsorption,and the magnetization axis will turn from the surface to the surface,but the magnetic field is still antiferromagnetic.