Magneto-optical effect of MO recording media and the development of new materials

1.稀土（RE）-过渡金属（TM）非晶合金薄膜的磁光效应（1）制备了Yb-Co非晶合金薄膜，并测量了其磁光特性。估计Yb原子变成2+离子而不是3+离子。结果表明，Yb原子在Yb-Co合金中没有磁矩，其磁性和磁光性能与La-Co和Ce-Co薄膜非常相似。(2)研究了Gd含量从10到50原子当量的Gd-Co薄膜的磁光克尔效应。与其它稀土物种不同，Co的原子磁矩随Gd含量的增加而略有减小，这导致了在Gd含量较高时，Co的克尔旋转相对较大。通过分析Kerr旋转系数的组分依赖性，分离了Gd和Co两个子网络磁化强度的贡献，并在波长范围内确定了Kerr旋转系数的谱。 关于我们 th从400到1, 000 nm。(3)利用现有的数据，包括目前的项目研究，澄清了除RE=Eu的RE-TM非晶合金的磁结构。(4)对于磁光存储的重要介质RE-Fe_ Co_合金薄膜，分离了RE和TM子网络对克尔旋转谱的贡献<0.8><0.2>. Mn化合物和/或多层膜新型磁光材料的开发研究（1）发现MnBi膜在低温下的克尔旋转显著增加，这是现有理论无法解释的。根据克尔旋转、克尔椭圆率、光学反射率和光学透射率的数据，计算了85、300和475 K下230- 1600 nm波长范围内介电常数张量各分量的光谱。从电子结构的角度讨论了克尔效应的物理根源。结果表明，MnBi中的巨克尔旋转是由Mn的3d ~* 到3d ~* 自旋态的带间跃迁引起的. (2)至于开发新的锰化合物和/或人工超结构，尚未获得任何显著的数据，该项目仍有待进一步研究。少

1. Magneto-optical effects of rare earth (RE)-transition metal (TM) amorphous alloy films (1) Yb-Co amorphous alloy films are prepared, and the magnetic and magneto-optical properties are measured. It is estimated that the Yb atoms become 2+ ions instead of 3+. As the results, Yb atoms have no magnetic moment in the Yb-Co alloy and the magnetic and magneto-optical properties are very similar to those for La-Co and/or Ce-Co films.(2) The magneto-optical Kerr effect is investigated for Gd-Co films with wide range of Gd content from 10 to 50 atomic percents. Different from other RE species, the atomic moment of Co decreases only slightly with the increase of Gd content, the fact which results in the relatively large Kerr rotation at higher Gd concentration. By analyzing the compositional dependence of the Kerr rotation, the contributions from both Gd and Co sub network magnetizations are separated and the spectra of the Kerr rotation coefficient are determined within the range of waveleng … More th from 400 to 1,000nm.(3) The magnetic structures of RE-TM amorphous alloys except RE=Eu are clarified using all available data including present project studies.(4) The contributions of RE and TM sub networks on the Kerr rotation spectra are separated for RE-Fe_<0.8>Co_<0.2> alloy films, which are important media for magneto-optical memory.2. Studies on the development of new magneto-optical materials of Mn compound and/or multilayrs(1) A remarkable increase of Kerr rotation at low temperature, which cannot be explained by the existing theory, is found for MnBi films. The spectra of all components of dielectric constant tensor are calculated in the wavelength range of 230-1600nm at 85,300, and 475K from the data on the Kerr rotation, the Kerr ellipticity, optical reflectivity, and optical transmittance. The physical origins of the Kerr effect are discussed from the viewpoint of electronic structure. It is concluded that the giant Kerr rotation in MnBi is originated from the interband transition from 3d * to 3d * spin states of Mn.(2) As for the development of new Mn compounds and/or artificial superstructures, any remarkable data have not yet been obtained, and the project is remained for further investigations. Less