Saturation magnetization of ferromagnetic and ferrimagnetic nanocrystals at room temperature

Abstract

The size-dependent saturation magnetization Ms(D) of ferromagnetic and ferrimagnetic nanocrystals at room temperature, without free parameters, has been predicted in terms of a size-dependent cohesive energy model, where D denotes the diameter of nanoparticles or the thickness of thin films. The given Ms(D) functions, which are also a function of interface conditions for substrate supported nanocrystals, drop as D decreases, which correspond to the available experimental and theoretical results for ferromagnetic Ni films, Fe, Co, Ni nanoparticles, and ferrimagnetic γ-Fe2O3, Fe3O4, MnFe2O4 and CoFe2O4 nanoparticles.