Flux Growth and Magnetic Properties of Single Crystals of Hexagonal Ferrite Structures and a Long-Range-Order Structure

We prepared single crystals of six typical hexaferrites (M-type, W-type, X-type, Y-type, Z-type, and U-type) in order to investigate their formation, crystal size, and magnetic properties. In addition, we also investigated the conditions of single-crystal formation at several flux concentrations and cooling rates. We found that the growth of single crystals on the MY-line (Y- and Z-type) became more significant than that on the MS-line (W-type) under a slow-cooling condition. In contrast, the single crystals on the MS-line appeared with a relatively high cooling rate of 10°C/h., where the single crystals did not grow large. By using the self-flux method, we succeeded in synthesizing single crystals with a more complex structure with a possibility of being M2Y7 on the MY-line and investigating the magnetic properties.