Analyses of Magnetic Force Images of Submicron Magnetic Mn-Ga Particles

The sample was prepared by implanting Mn⁺ ions at energy of 80keV and Mn⁺ ions of dose of 2 x 10¹⁷/cm² directly into the semi-insulating (100) GaAs wafer, followed by rapid annealing at 830°C for 90s. By using magnetic force microscopy, both the topographic and magnetic force images of the submicron particles in the surface layer of the sample were obtained. The formation of the magnetic particles is more complex, corresponding to more types of magnetic force image patterns. Computer simulation was carried out by integrating the interactions between the tip and the particles, which can be used to judge the magnetization direction of particles more accurately. Moreover, the simulation has confirmed that all submicron magnetic particles are single crystals with a single domain. In fact, the simulated patterns of the single-domain particles are the “elemental” magnetic force patterns for magnetic materials, hence their acquirement and collection are the basis of the analysis and explanation of magnetic force images.