ABSTRACT

First-principles calculation based on density functional theory is a powerful tool for understanding and designing magnetic materials. It enables us to quantitatively describe magnetic properties and structural stability, although further methodological developments for the treatment of strongly correlated 4f electrons and finite-temperature magnetism are needed. Here, we review recent developments of computational schemes for rare-earth magnet compounds, and summarize our theoretical studies on Nd₂Fe₁₄B and RFe₁₂-type compounds. Effects of chemical substitution and interstitial dopants are clarified. We also discuss how data-driven approaches are used for studying multinary systems. Chemical composition can be optimized with fewer trials by the Bayesian optimization. We also present a data-assimilation method for predicting finite-temperature magnetization in wide composition space by integrating computational and experimental data.

摘要

基于密度泛函理论的第一性原理计算是理解和设计磁性材料的有力工具。它使我们能够定量描述磁性和结构稳定性，尽管需要进一步开发处理强相关 4f 电子和有限温度磁性的方法。在这里，我们回顾了稀土磁体化合物计算方案的最新进展，并总结了我们对 Nd ₂ Fe ₁₄ B 和R Fe _{12 的}理论研究- 型化合物。阐明了化学取代和间隙掺杂剂的影响。我们还讨论了如何使用数据驱动的方法来研究多元系统。通过贝叶斯优化，可以通过较少的试验来优化化学成分。我们还提出了一种数据同化方法，通过整合计算和实验数据来预测宽组成空间中的有限温度磁化强度。