Российский технологический журнал (Oct 2020)
Methods of effective media as optimal methods for modeling the physical properties of nanostructures
Abstract
This paper considers various methods of effective media as a tool for studying both optical and magneto-optical properties of various nanostructures, primarily magnetic nanostructures. Formulas for finding diagonal and non-diagonal components of the permittivity tensor for all basic approximations of the effective medium were obtained explicitly. These formulas are valid for both nanocomposites and granular alloys. The possibility of predicting various optical and magneto-optical properties of such structures is discussed using the example of the transverse Kerr effect as a promising non-contact method for studying nanostructures for a ferromagnetic nanocomposite (CoFeZr)x(MgF2)100-x. A possible application of the obtained formulas is discussed. Various methods of effective media make it possible to study nanostructures in a wide range of values of the concentration of the metal (magnetic) component Х. The paper notes and discusses the contribution of various mechanisms that affect the physical properties of such structures, especially in the IR region of the spectrum, where the quasi-classical dimensional effect is most pronounced. The form factor of nanocomposite particles and the average particle size are such contributions that can be taken into account. The contribution of the quasi-classical dimensional effect to the diagonal and non-diagonal components of the structure's permittivity tensor is analyzed within the framework of the Drude-Lorentz model. The problem being solved in this work is relevant, since interesting and important effects are observed in magnetic nanostructures, such as the Kerr effect, anomalous absorption, giant magnetoresistance, tunnel magnetoresistance, and many others. These effects play an important role in modern electronic devices, which makes this work particularly relevant.
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