Research of Ultra High Density Magneto-optical Recording Material

从诱导各向异性的角度估计了[111]取向多晶PdCo和PtCo合金膜和多层膜的磁致伸缩常数lambda_<111>和lambda_<100>。结果表明，Pd/Co和Pt/Co合金的磁致伸缩常数不受fcc Co合金的磁致伸缩常数的影响，而受PdCo和PtCo合金的磁致伸缩常数的影响较大。这一结果暗示了电子杂化和/或合金在界面处形成的影响。测量了超薄钴薄膜的磁光克尔磁滞回线及其能谱。在Au/ 20a / Co/Au夹层中，克尔旋转和克尔椭圆度的光谱形状与体数据计算结果一致。随着Co厚度的减小，光谱形状与计算值有所不同。对超薄Co薄膜的非对角电导率的虚值也进行了估计。研究了用射频溅射法制备的nddd /Fe和nddd /FeCo多层材料的磁性和磁光性能。在10 ~ 15 a的双层周期内，垂直磁各向异性的最大值约为2.5 X 10^6 erg/cm^3。多层膜的磁光Kerr旋转达到0.33 400 nm，反映了Nd的贡献。

Magnetostriciton constants lambda_<111> and lambda_<100> were estimated for [111] oriented polycrystalline PdCo and PtCo alloy films and multilayr films (MLs) from the induced anisotropy. It was found that the mangetostriction constants of Pd/Co and Pt/Co MLs are not determined by the mangetostriction constants of fcc Co, but are strongly affected by those of PdCo and PtCo alloys. This result implies the effect of electron hybridization and/or alloy formation at the interface.Magneto-optical Kerr hysteresis loops and their energy spectra are measured for ultrathin Co films. In Au/20 A Co/Au sandwiches, the spectra shape of the Kerr rotation as well as the Kerr ellipticity agrees with those calculated from bulk data. With decreasing Co thickness, the spectral shape becomes different from the calculated one. The imaginary prot of off-diagonal conductivity was also estimated for ultrathin Co films.Magnetic and magnetooptic properties have been investigated for NdGd/Fe and NdGd/FeCo multilayrs prepared by rf sputtering method. At a bilayr period of 10 to 15 A, perpendicular magnetic anisotropy showed the maximum value of about 2.5 X 10^6 erg/cm^3. Magnetooptic Kerr rotation of the multilayrs reach 0.33ﾟ at 400 nm, reflecting the contribution of Nd.