Magnetic nanocomposites: new methodology for micromagnetic modeling and SANS experiments

TL;DR

This paper introduces a novel micromagnetic simulation method tailored for two-phase magnetic nanocomposites, enabling efficient modeling of soft and hard phases and validated by SANS experiments on iron-based alloys.

Contribution

The paper presents a new simulation approach that avoids discretizing hard inclusions, improving modeling efficiency for magnetic nanocomposites.

Findings

Simulation results match experimental SANS data.

Method accurately predicts equilibrium magnetization states.

Applicable to complex two-phase magnetic materials.

Abstract

A new methodology for micromagnetic simulations of magnetic nanocomposites is presented. The methodology is especially suitable for simulations of two-phase composites consisting of magnetically hard inclusions in a soft magnetic matrix phase. The proposed technique allows to avoid the unnecessary discretization of the 'hard' inclusions (these are normally in a single-domain state), but enables an arbitrary fine discretization of the 'soft' phase. The method is applied to the determination of the equilibrium magnetization state of an iron-based nanocomposite from the Nanoperm (FeZrBCu) family of alloys and to the calculation of the corresponding small-angle neutron scattering (SANS) cross-section. For this highly interesting material, the results of our simulations exhibit a remarkable agreement with the nontrivial 'clover-leaf' SANS cross-sections observed experimentally (A. Michels et al., Phys. Rev. B, v. 74, 134407 (2006)).