Abstract
Correlations between magnetic and crystallographic domains in an ordered double perovskite, Ba2FeMoO6, were investigated by transmission electron microscopy. We found that magnetic domain walls perfectly coincide with crystallographic antiphase domain boundaries. This suggests a pinning effect on the magnetic domains at the antiphase boundaries. In addition, we observed a magnetic nanodomain structure derived from coupling between magnetic and structural ordering domains where Fe/Mo short-range ordering was developed. The magnetic domain structure in the ordered double perovskite is significantly affected by the crystallographic structures, i.e., the antiphase boundary and the short-range ordering, due to their strong mutual coupling.