| Due to the problems of energy loss and integrated electronic technology,the research on new information transmission has wide application prospect.Spin wave transmits information through electronic spin coding,so it can overcome the problems of heat energy consuming,which means that it is of great significance to study the excitation and control of spin wave.In this thesis,the influence of magnetic exchange interaction on spin waves in magnetic films has been studied.In order to study the spin wave resonance,the exchange effect was changed by doping non-metallic elements in the single thin film and ferromagnetic coupling.Firstly,FeCoB films with different B content and different thicknesses were deposited by composition gradient sputtering.The spin dynamics of FeCoB films has been studied systematically.We explored the static magnetic properties and spin wave resonance induced via the variation of the B component in FeCoB films and FeCoB film thickness.Secondly,yttrium iron garnet(YIG)target was prepared by solid sintering,and GGG/YIG single crystal thin films with nanometer thickness were grown by using pulse laser deposition method.In addition,the effects of different growth conditions on the crystallinity and magnetic properties of GGG/YIG films were investigated.A series of GGG/YIG/Co heterostructures with different thickness of GGG/YIG were prepared under suitable growth conditions,and the spin wave resonance of GGG/YIG/Co heterostructures was studied.The main research work is as follows.1.The effects of B content and film thickness on the magnetic properties and standing spin wave resonance in FeCoB films were studied.Firstly,FeCoB films with different B doping content were prepared by composition gradient sputtering method.The results showed that B contents can affect the in-plane uniaxial magnetic anisotropy in FeCoB films.Besides,different B composition gradients can also affect the magnetic exchange interaction of thin films,which changes the exchange constants.As a result,high order perpendicular standing spin waves can be observed in FeCoB films.Secondly,FeCoB thin films with different thickness were prepared by composition gradient sputtering.By analyzing the hysteresis loop and related ferromagnetic resonance,the influence of thickness on the magnetic anisotropy and perpendicular standing spin waves has been studied.We found that thickness variation of thin films can affect the in-plane uniaxial magnetic anisotropy and magnetic exchange interaction,and thus influence the excitation of perpendicular standing spin waves in the films.2.Ferromagnetic resonance and spin wave resonance were studied in GGG/YIG single crystal thin film and GGG/YIG/Co heterostructures.Firstly,YIG target was prepared by solid sintering,and GGG/YIG single crystal thin films with different laser frequency,oxygen pressure and substrate temperature were grown by using pulse laser deposition method.The structure and static magnetism of the film were studied as well as dynamic magnetism.Secondly,GGG/YIG single thin films with different thicknesses and GGG/YIG/Co heterostructures were prepared,and the effect of exchange coupling between layers on the standing spin waves was studied. |
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