ABSTRACT
This chapter discusses the magnetic anisotropy of magnetic nanocomposites consisting of nanoparticles with magnetic ordering, having atomic magnetic moments aligned under the exchange or superexchange interaction, namely ferro- and ferrimagnetic. It presents the magnetic anisotropy of magnetic nanocomposites made of ferro- and ferrimagnetic nanoparticles, large or smal, and those with a superparamagnetic behavior, dispersed in solid matrices. The chapter explores the important physical aspects regarding magnetic anisotropy, magneto-crystalline anisotropy, surface anisotropy, shape anisotropy and the induced anisotropy by stress and the exchange coupling. It describes the temperature dependence of the magnetocrystalline anisotropy constants, as well as the ferromagnetic resonance method, used in research laboratories for accurate experimental determination of the magnetic anisotropy constants. The chapter shows the importance of knowing the magnetic anisotropy of the nanocomposites made of nanoparticles dispersed in solid matrices, in terms of advanced applications in nano- and biotechnology.
