Compensated ferrimagnetic insulators are particularly interesting for enabling functional spintronic,optical,and microwave devices.Among many different garnets,Gd_(3)Fe_(5)O_(12)(GdIG)is a representative compensated f...Compensated ferrimagnetic insulators are particularly interesting for enabling functional spintronic,optical,and microwave devices.Among many different garnets,Gd_(3)Fe_(5)O_(12)(GdIG)is a representative compensated ferrimagnetic insulator.In this paper,we will study the evolution of the surface morphology,the magnetic properties,and the magnetization compensation through changing the following parameters:the annealing temperature,the growth temperature,the annealing duration,and the choice of different single crystalline garnet substrates.Our objective is to find the optimized growth condition of the GdIG films,for the purpose of achieving a strong perpendicular magnetic anisotropy(PMA)and a flat surface,together with a small effective damping parameter.Through our experiments,we have found that the surface roughness approaching 0.15 nm can be obtained by choosing the growth temperature around 700℃,together with an enhanced PMA.We have also found the modulation of magnetic anisotropy by choosing different single crystalline garnet substrates which change the tensile strain to the compressive strain.A measure of the effective magnetic damping parameter(α_(eff)=0.04±0.01)through a spin pumping experiment in a GdIG/Pt bilayer is also made.Through optimizing the growth dynamics of GdIG films,our results could be useful for synthesizing garnet films with a PMA,which could be beneficial for the future development of ferrimagnetic spintronics.展开更多
The Ca-Sn co-substituted yttrium iron garnet(YIG)ferrite materials were prepared by the traditional oxide solid-state reaction method,and the influence of forming pressure on the density,morphology and magnetic proper...The Ca-Sn co-substituted yttrium iron garnet(YIG)ferrite materials were prepared by the traditional oxide solid-state reaction method,and the influence of forming pressure on the density,morphology and magnetic properties of YIG ferrite was systematically studied.The results show that the density of YIG ferrite green body increases with the increase of the forming pressure,while the density of its sintered body shows a trend of first increasing and then decreasing.At the same time,the ferromagnetic resonance(FMR)linewidth of YIG sample first decreases and then increases.Meanwhile,the effects of forming pressure on the saturation magnetization,remanence and coercivity of the sample can be ignored.This study proves that the density and FMR linewidth of YIG materials can be controlled by regulating the forming pressure and the best performance is obtained for the sample prepared under a forming pressure of 5 MPa.展开更多
基金Project supported by the National Key R&D Program of China(Grant Nos.2017YFA0206200 and 2016YFA0302300)the Basic Science Center Project of the National Natural Science Foundation of China(Grant No.51788104)+2 种基金the National Natural Science Foundation of China(Grant Nos.11774194,11804182,51831005,and 11811082)Beijing Natural Science Foundation(Grant No.Z190009)the Beijing Advanced Innovation Center for Future Chip(ICFC).
文摘Compensated ferrimagnetic insulators are particularly interesting for enabling functional spintronic,optical,and microwave devices.Among many different garnets,Gd_(3)Fe_(5)O_(12)(GdIG)is a representative compensated ferrimagnetic insulator.In this paper,we will study the evolution of the surface morphology,the magnetic properties,and the magnetization compensation through changing the following parameters:the annealing temperature,the growth temperature,the annealing duration,and the choice of different single crystalline garnet substrates.Our objective is to find the optimized growth condition of the GdIG films,for the purpose of achieving a strong perpendicular magnetic anisotropy(PMA)and a flat surface,together with a small effective damping parameter.Through our experiments,we have found that the surface roughness approaching 0.15 nm can be obtained by choosing the growth temperature around 700℃,together with an enhanced PMA.We have also found the modulation of magnetic anisotropy by choosing different single crystalline garnet substrates which change the tensile strain to the compressive strain.A measure of the effective magnetic damping parameter(α_(eff)=0.04±0.01)through a spin pumping experiment in a GdIG/Pt bilayer is also made.Through optimizing the growth dynamics of GdIG films,our results could be useful for synthesizing garnet films with a PMA,which could be beneficial for the future development of ferrimagnetic spintronics.
文摘The Ca-Sn co-substituted yttrium iron garnet(YIG)ferrite materials were prepared by the traditional oxide solid-state reaction method,and the influence of forming pressure on the density,morphology and magnetic properties of YIG ferrite was systematically studied.The results show that the density of YIG ferrite green body increases with the increase of the forming pressure,while the density of its sintered body shows a trend of first increasing and then decreasing.At the same time,the ferromagnetic resonance(FMR)linewidth of YIG sample first decreases and then increases.Meanwhile,the effects of forming pressure on the saturation magnetization,remanence and coercivity of the sample can be ignored.This study proves that the density and FMR linewidth of YIG materials can be controlled by regulating the forming pressure and the best performance is obtained for the sample prepared under a forming pressure of 5 MPa.