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

1.稀土(RE)-过渡金属(TM)非晶态合金薄膜的磁光效应(1)制备了Yb-Co非晶态合金薄膜，并测量了薄膜的磁性和磁光性能。据估计，Yb原子变成了2个离子，而不是3个。结果表明，Yb原子在Yb-Co合金中没有磁矩，其磁学和磁光性质与La-Co和/或Ce-Co薄膜非常相似。(2)研究了Gd含量从10%到50%范围内的Gd-Co薄膜的磁光克尔效应。与其他稀土物种不同，Co的原子矩仅随Gd含量的增加而略有减小，这导致了较高Gd含量时较大的克尔转角。通过分析克尔旋转的成分依赖关系，分离了Gd和Co亚网络磁化的贡献，并在波长…范围内确定了克尔旋转系数的谱(3)利用包括本项目研究在内的所有现有数据，阐明了除RE=Eu以外的RE-Tm非晶态合金的磁结构。(4)分离了RE-Fe_&lt；0.8&gt；Co_&lt；0.2&gt；合金薄膜这一重要的磁光存储介质的RE-Fe_&lt；0.8&gt；Co_&lt；0.2&gt；合金薄膜的克尔转角光谱。研究了锰化合物和/或多层膜的新型磁光材料的发展。(1)在低温下，发现了用现有理论无法解释的明显的克尔旋转。根据克尔旋转、克尔椭圆率、光学反射率和光学透过率的数据，计算了85、300和475K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起源。由此可以得出结论：MnBi3d*到3d*自旋态的带间跃迁是导致MnBi3d*向3d*自旋态转变的主要原因。(2)关于新的Mn化合物和/或人工超结构的发展，目前还没有得到任何有意义的数据，有待于进一步研究。较少

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