用热分解法制备的Bi,Al替DyIG磁光薄膜虽然是纳米晶,但由于其晶界分布不均匀、晶粒较大且均匀性差,当用于磁光记录时,晶界将产生较大的噪音.而掺Rb的Bi,Al替DyIG磁光薄膜不仅可以降低晶化温度,而且晶粒明显细化,最大晶粒尺寸从100 nm下降到50 nm左右,平均晶粒尺寸下降为30 nm左右.并且晶粒的均匀性明显改善,掺入的Rb以Rb2O固溶体的形式存在于磁光薄膜表面,填补了薄膜表面的凹凸不平,使薄膜表面反射率增加,信噪比增大.因此掺Rb可使纳米晶Bi,Al替DyIG磁光薄膜的性能大大提高.

Though Bi, Al substituted Dy-iron garnet films for magneto-optical recording prepared by pyrolysis are nanocrystalline, but because the imhomogeneity of grain boundaries, the sizes of the grains are bigger and imhomogeneity, there is a serious problem of media noise in magneto-optical recording. While Bi, Al substituted Dy-iron garnet films for magneto-optical recording with Rb-doping not only decreased the crystallized temperature, but also decreased the grains sizes. The biggest grain size from 100 nm decreased to about 50 nm, average grains size decreased to about 30 nm, and the homogeneity of the grains was improved. The reflecting of the surface increased because of the doped Rb existed on the surface of the films in form of Rb2O condensate filling the surface curves. The signal to noise improved. So Rb-doping can greatly improved the magneto-optical characteristics of Dy-iron garnet films for magneto-optical recording.