Features of the magnetorefractive effect in Co–Si nanocomposites

Objectives. The work set out to study the spectra of the magnetorefractive effect (MRE) in the cobalt–silicon (Co–Si) nanocomposite, taking into account the contribution of the size effect(SE), and to compare the results obtained by varying the parameters of the SE. The presented approaches to investigating the magnetooptical properties of nanocomposites, which are relevant for the practical application of nondestructive testing methods, have the potential to significantly increase the efficiency of their use in various fields, including spintronics and optics.
Methods. Computer modeling approaches based on the Bruggeman approximation are used to model the examined structure as a medium with effective properties.
Results. MRE spectra obtained within the framework of the modeling fell within the range of 0.5–3.5 eV. The modeling was carried out for MRE both with and without taking into account the semiclassical size effect. The resultant modeling of the spectral dependencies of the MRE is based on the example of a Co–Si nanocomposite at different cobalt particle sizes and form factors. The influence of size effects on the form of the MRE spectra is confirmed. The reliability of the methods is confirmed by a comparison of the obtained results with empirical data. The value of the obtained results consists in the good agreement of all the calculated parameters of the discussed nanocomposite and the form of the spectral dependencies of the MRE with the results of various experiments.
Conclusions. The confirmation that both the size and form factor of granules have a significant impact on the appearance of the MRE spectra raises the prospect of developing promising nanocomposite properties at particular particle sizes. The presented results highlight the possibility of optimizing the material characteristics to improve sensitivity in magnetic sensors and noncontact devices for studying nanostructures.

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