Co/Ti金属磁性多层膜的激光布里渊散射研究(英文)  

Co/Ti magnetic multilayer films investigated by Brillouin light scattering

作　　者：刘玉龙[1] 萧季驹[2] 

机构地区：[1]中国科学院物理研究所光物理开放实验室,北京100080 [2]香港城市大学物理及材料科学系

出　　处：《光散射学报》2002年第1期20-26,共7页The Journal of Light Scattering

摘　　要：在室温下利用直流磁控溅射法制备出了具有不同Co层厚度的 [Co(dConm) /Ti(dTinm) ]n 金属磁性多层膜 (其中dCoanddTi是Co和Ti的厚度 ,n薄膜调制周期数 )。在 30 0K下用X射线衍射法 (XRD)和布里渊散射方法研究了Co层厚度分别为dCo=1 ,2 ,2 5 ,3 5nm ,Ti层厚度为dTi=2 5nm的Co/Ti多层膜。XRD的结果所示在Co/Ti多层膜中Co层厚度超过 2 5nm ,其结构类似块材Co的多晶结构。对比之下 ,Co/Ti多层膜中Co层厚度低于 2 5nm ,其XRD衍射峰随Co层厚度减少变的峰形加宽 ,衍射峰的强度减少 ,峰位移动和消失。在Co/Ti多层膜中自旋波的布里渊散射结果表明 :在Co/Ti多层膜中 ,对于dCo>2 5nm磁性呈铁磁性耦合 ,在dCo≤ 2 5nm时 ,其呈反铁磁性耦合。除表面自旋波外 ,在呈反铁磁性耦合的材料中观测到了两个有体特征的自旋波 ,而在呈铁磁耦合的材料中只观测到一个有体特征的自旋波。Co(d Co nm)/Ti(d Ti nm)] n (both d Co and d Ti are the thicknesses of Co and Ti sublayers, respectively n is the number of modulation periods ) magnetic multilayer films (MMLFs) with different Co sublayer thicknesses are prepared at room temperature by the dc magnetron sputtering technique Co/Ti MMLFs (d Co =1,2, 2 5 and 3 5 nm, d Ti =2 5 nm) are investigated using x ray diffraction (XRD) and Brillouin light scattering (BLS) from spin waves at 300 K XRD of the MMLFs with Co sublayer thicknesses exceeding 2 5 nm are similar to the polycrystalline structures of bulk Co On the contrary, those of the films with Co sublayer thicknesses below 2 5 nm are deteriorated crystalline spectra with spectroscopic peak broadening, peak intensity reducing, position shifting and merging BLD results from spin waves in Co/Ti MMlfs show ferromagnetic coupling for d Co >2 5 nm, and antiferromagnetic coupling between adjacent Co layers for d Co ≤2 5 nm Besids a surface character spin wave, two bulk character spin wave bands are observed for antiferromagnetic films, but only one band for the ferromagnetic film

关 键 词：Co/Ti 金属磁性多层膜 激光布里渊散射 光学性质 钴 钛 

分 类 号：O484.43[理学—固体物理] O484.41[理学—物理]