INVESTIGATION OF DOMAIN WALLS IN THIN SECTIONS OF IRON BY ELECTRON INTERFERENCE METHOD

Domain wall widths are measured in several types of iron thin section by examination of the contrast occurring at convergent walls when they are imaged by the technique of out-of-focus Lorentz electron microscopy. Images of 90° domain walls in single crystal iron films with surfaces parallel to the (100) plane, 90° and 180° walls in similarly oriented foils of SiFe and walls in polycrystalline films have been observed experimentally. The theoretical wall image intensity profiles are calculated from a wave optical model by means of a digital computer. Changes in the computed image with various domain wall magnetization rotation distributions and with changes in domain wall width and illuminating beam divergence are investigated. A procedure is described for comparing theoretical and experimental images which enables values for the domain wall widths to be deduced. © 1969 Taylor & Francis Group, LLC.