论文部分内容阅读
@@ The micro magnetic structures and magnetization processes of perpendicularly-oriented Y3Fe5O12 (yttrium ion garnet: YIG) films were studied using Lorentz microscopy and electron holography [1]. The closure magnetic domain structure inside the thin specimens of transmission electron microscope (TEM) exhibits the same period as that of the magnetization pattern observed by magnetic force microscopy,indicating the perpendicular anisotropy characteristic of the YIG film. Observation of stray magnetic fields outside the sample shows that the shapes of domains and domain walls are sensitive to the specimen thickness. In addition, a closure domain configuration observed in thin specimens is the energetically stable state determined by the balance between the crystalline anisotropy energy and shape anisotropy energy.