Multiferroic behavior of ferrites

Abstract

Multiferroic materials are the one which possess at least two long-range ferroic orderings (ferromagnetic or antiferromagnetic, ferroelectric, and ferroelastic) simultaneously in a single phase. There are two types of multiferroics: (1) type-I multiferroics, where magnetism and ferroelectricity have distinct origins, and (2) type-II multiferroics, where ferroelectricity originates from the internal magnetism of the system. Multiferroicity is a rare phenomenon due to the requirement of two seemingly exclusive orderings to be present simultaneously, but the existence of this phenomenon in spinel ferrites is even rarer. In this chapter, we provide a brief overview of spinel ferrite multiferroic systems to understand their multiferroic behavior, their origin, and response mechanisms. A discussion of a few known spinel ferrites multiferroic materials, such as Fe3O4 and NiFe2O4, is depicted in this chapter.