Magnetism and magnetoelectricity of a U-type hexaferrite Sr4Co2Fe36O60

We report on structural, magnetic, and magnetoelectric (ME) properties of a U-type hexaferrite Sr4Co2Fe36O60 prepared by solid state reaction. Samples sintered at 1150–1180 °C in oxygen contain the fewest impurity phases and show highly insulating behavior. Powder neutron diffraction results reveal that a commensurate magnetic order with a (0,0,3/2) propagation vector develops below TN2∼350 K. Corresponding to the appearance of the magnetic order, the sample shows a small ME effect. These results suggest that Sr4Co2Fe36O60 is a room-temperature ME material in which the origin of the ME effect is similar to those of other ME hexaferrites.