Magnetocrystalline anisotropy and spin-wave stiffness in tensilestrained La_(0.67)Ba_(0.33)MnO_3 films:An investigation via ferromagnetic resonance  

作　　者：DUANMU QingYong TONG Wei YANG Lei HAO Lin ZHANG ZhongFeng WANG XiaoPing ZHU Hong 

机构地区：[1]Department of Physics,University of Science and Technology of China [2]High Magnetic Field Laboratory,Chinese Academy of Sciences

出　　处：《Chinese Science Bulletin》2013年第33期4057-4063,共7页

基　　金：supported by the National Natural Science Foundation of China (11174261)

摘　　要：Tensile-strained epitaxial La0.67Ba0.33MnO3(LBMO)film has been prepared by magnetron sputtering technique on(001)oriented spinel MgAl2O4substrate.The transport and magnetic measurements give an insulator-metal transition and paramagnetic-ferromagnetic transition occurring at^150 K and 250 K respectively,which implies the phase separation in such a tensile-strained film.By analyzing the angular and temperature dependences of the ferromagnetic resonance(FMR),we determine the magnetocrystalline anisotropy of the film.It is found that the tensile-strained film is dominated by an easy-axis corresponding to the compressive out-of-plane direction,though the magnitudes of anisotropy constants are relatively small and their temperature dependences are some complex.Furthermore,the FMR spectra show additional spin wave resonance(SWR),and the field positions can be indexed to follow a linear dependence on the square of index n.The scaling gives a spin-wave exchange stiffness D of 20.7 meV 2at low temperature,which is less than half of that in strain-free LBMO films,implying that the double exchange interaction is remarkably suppressed in the tensile-strained LBMO films.Tensile-strained epitaxial La0.67Ba0.33MnO3 （LBMO） film has been prepared by magnetron sputtering technique on （001） oriented spinel MgAl2O4 substrate. The transport and magnetic measurements give an insulator-metal transition and paramagnetic-ferro- magnetic transition occurring at -150 K and 250 K respectively, which implies the phase separation in such a tensile-strained film By analyzing the angular and temperature dependences of the ferromagnetic resonance （FMR）, we determine the magnetocrystal- line anisotropy of the film. It is found that the tensile-strained film is dominated by an easy-axis corresponding to the compressive out-of-plane direction, though the magnitudes of anisotropy constants are relatively small and their temperature dependences are some complex. Furthermore, the FMR spectra show additional spin wave resonance （SWR）, and the field positions can be in- dexed to follow a linear dependence on the square of index n. The scaling gives a spin-wave exchange stiffness D of 20.7 meV A 2 at low temperature, which is less than half of that in strain-free LBMO films, implying that the double exchange interaction is remarkably suppressed in the tensile-strained LBMO films.

关 键 词：磁晶各向异性 自旋波共振 拉伸应变 铁磁谐振 镁铝尖晶石 温度依赖性 劲度 磁控溅射技术 

分 类 号：O484[理学—固体物理]