Ferroika
Ferroika (from Latin : ferrum = iron) is the generic term for all materials with a spontaneous long-range order. The group of ferroic ordering phenomena includes ferromagnetism , ferroelectricity , ferroelasticity and ferrotoroidicity .
If two or more of the ferroic order phenomena occur simultaneously in a substance, one speaks of a higher order ferroica or multiferroica . Ferroica are therefore of the order one, if there are two orders there is a second order ferroic.
The term Ferroika was introduced in 1970 by the Japanese physicist K. Aizu . The aim was a systematic description and classification of ferromagnetic , ferroelectric and ferroelastic materials, which was essentially based on arguments of symmetry. More recently, ferrotoroidity has been added as the fourth ferroic order.
Individual evidence
- ↑ K. Aizu, Possible Species of Ferromagnetic, Ferroelectric, and Ferroelastic Crystals , Phys. Rev. B, 2, 754, 1970 .