The Properties Of Ferromagnetic Resonance In Magnetic Thin Film Under The Stress Field

Layered magnetic thin film which is deposited by two or more different materials in a suitable substrate is a multilayer structure of magnetic thin film. In recent years, Multilayer magnetic thin film material is widely used in magnetic tunnel junction, spin valve and spin switch and so on, So it is necessary to understand its basic physical properties.The theory of minimum energy has been used to study the ferromagnetic resonance (FMR) characteristics of magnetic thin film system. And based on the theory of Smith and Beljers, the analytical expression of the ferromagnetic resonance frequency were derived. Resonance frequency which changed along with the magnetic field is given. First, the external magnetic field which is perpendicular to the x-y surface and along the z axial direction are discussed in this paper.Resonance frequency curve and the magnetization curve are influenced by stress anisotropy, cubic anisotropy and the exchange anisotropy. The numerical calculation results shown that:The increase of cubic anisotropy field and the exchange anisotropy field block plane magnetization and promote its vertical magnetization. The second, when the external magnetic field along the x-y plane, resonance frequency curve and the magnetization curve are influenced by stress anisotropy. In this paper, when stress field is weak, the spectrum width are greatly influenced by the direction of external stress field. Resonance frequency is dependent on the intensity and the direction of external stress field.