Computer simulation of Lorentz electron micrographs of thin magnetic particles

摘要

Lorentz electron microscopy is a powerful tool for high-resolution studies of magnetic structures, not only in continuous thin films, but also in spatially limited, i.e. individual particles. In addition to the experimental studies of magnetic particulate media it is interesting to simulate images in order to compare them with experimental results, as it is practiced in high-resolution electron microscopy. This paper introduces a software package which simulates the Lorentz microscopical image of magnetic structures in thin particles. While other simulation programs deal with infinite magnetic films with homogeneous thickness, the major difference in our calculation is that we take into account the finite dimensions of the particle for specimens of various sizes and shapes. That means the phase shift due to the inner potential depending on the geometrical shape of a magnetic particle is added to the phase shift depending on its magnetic microstructure. The following article presents the computation methods and its results and compares it with experimental findings.