We investigated the occurrence of magnetic domains in MnZn-ferrite grains by magnetic force microscopy ͑MFM͒. At the surface of samples with different grain sizes in the range from 2 to 10 m, small grains generally contain only one domain, while large grains contain two domains. The crossover between these two intragranular domain states occurs at a critical grain size D cr of about 4 m. This finding is in agreement with the conclusions from earlier neutron depolarization measurements on the same samples and reemphasizes the large discrepancy between theoretical calculations of D cr for isolated grains and experimental values in the ferrites. Furthermore, we find that the magnetic field profiles are not those expected from isolated grains. Modeling of the MFM response shows that the magnetic environment of a grain plays an important role in its magnetic configuration.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.