亚铁磁性 Ferrimagnetism

A ferrimagnetic material is a material that has populations of atoms with opposing magnetic moments, as in antiferromagnetism. For ferrimagnetic materials, these moments are unequal in magnitude so a spontaneous magnetization remains. This can for example occur when the populations consist of different atoms or ions (such as Fe2+ and Fe3+).

Ferrimagnetism has often been confused with ferromagnetism. The oldest known magnetic substance, magnetite (Fe3O4), was classified as a ferromagnet before Louis Néel discovered ferrimagnetism in 1948. Since the discovery, numerous uses have been found for ferrimagnetic materials, such as hard drive platters and biomedical applications.

参考资料:

https://en.wikipedia.org/wiki/Ferrimagnetism

https://zh.wikipedia.org/wiki/亚铁磁性

https://baike.baidu.com/item/亚铁磁性/1826296