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(dco nm)/Ti(dTi nm)].金属磁性多层膜(其中dcoand dTi是Co和TIi的厚度,n薄膜调制周期数).在300K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=1,2,2.5,3.5 nm,Ti层厚度为dTi=2.5 nm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2.5 nm,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2.5 nm,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≤2.5 nm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(dConm)/Ti(dTinm) ]n(both dCo and dTi are the thicknesses of Co and Ti sublayers, re-spectively. n is the number- of modulation periods. ) magnetic multilayer films (MMLFs) with differentCo sublayer thicknesses are prepared at room temperature by the dc magnetron sputtering technique.Co/Ti MMLFs (dco = 1,2, 2.5 and 3.5 nm, dTi = 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 Cosublayer thicknesses exceeding 2.5 nm are similar to the polycrystalline structures of bulk Co. On thecontrary, those of the films with Co sublayer thicknesses below 2.5 nm are deteriorated crystallinespectra with spectriscopic peak broadening, peak intensity reducing, position shifting and merging.BLD results from spin waves in Co/Ti MMlfs show ferromagnetic coupling for dco ＞2.5 nm, and antifearomagnetic coupling between adjacent Co layers for dco ≤2.5 nm. Besids a surface-character spinwave, two bulk-character spin wave bands are observed for antiferromagnetic films, but only one bandfor the ferromagnetic film.
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