Study on Effects of Dipole-dipole Interactions in Nd_2Fe_{14}B thin film Based on Stochastic Cut-off Method with New Efficient Algorithm

TL;DR

This paper introduces a new efficient algorithm for the stochastic cutoff Monte Carlo method, enabling detailed study of dipole interactions in Nd2Fe14B thin films, revealing the importance of Fe ion anisotropy on magnetization at high temperatures.

Contribution

A novel, efficient algorithm for the stochastic cutoff method tailored for complex lattice structures and high-temperature regimes.

Findings

Fe ion anisotropy is crucial for maintaining uniaxial magnetization at high temperatures.

The new algorithm improves computational efficiency for amorphous and complex unit cell materials.

The method enables detailed atomistic modeling of magnetic thin films with long-range interactions.

Abstract

We developed a new algorithm for the stochastic cutoff method, which is a Monte Carlo method for long-range interacting systems. The present new algorithm is efficient for complicated lattice structures, e.g., amorphous and also materials with complicated unit cell structure. In addition, it has an advantage in a high temperature region. With the present method, we investigated an atomistic model of the permanent magnet Nd 2 Fe 14 B with dipole-dipole interactions to study the effect of the anisotropy of the Fe ions on the magnetization structure in the thin film system. It has revealed that the anisotropy of the Fe ions plays an important role to maintain the uniaxial magnetization structure at high temperatures.