Micromagnetic Microscopy and Modeling

With the miniaturization of magnetic technologies, the need to understand magnetization on length scales below a micron is becoming increasingly important. This booming interest in micro magnetics has fueled a renaissance in both micro-magnetic modeling and measurement techniques. Conversely, the codevelop-ment of modeling and imaging has made possible recent advances in this critical area of magnetism. On the modeling side, the rapid development of high-speed computing has had a tremendous impact on micromagnetics simulations. On the measurement side, a number of microscopies have been developed for imaging on a length scale of tens of nanometers. Figure 1 shows an image of rows of bits in a magneto-optical medium. The bits were both written and imaged using a magnetic force microscope. Results on this length scale provide information that can be used in models and also challenge models’ predictive capabilities. The image on the cover of this issue shows naturally occurring domain patterns in a single-crystal ferrite, a system that exhibits extremely complex magnetic stmctures. The development of new imaging techniques and increasingly powerful computer simulations is rapidly advancing our understanding of magnetization at submicron scales—a regime of great interest to developers of magnetic technologies such as magneto-optical storage media.