基于二维Kagome点阵的磁性材料设计和数值模拟研究

A kagome lattice, composed of interlaced triangles in a two-dimensional (2D) pattern, is a well-known mathematical model widely used in the study of frustrated magnetism and assembled materials with exceptional mechanical properties or high Curie–Weiss temperature. In this project, a novel approach is provided for constructing a 2D periodic magnetic nanostructure by using magnetic triangular nanoflakes or plane molecules as the building blocks. The methods for design of 2D kagome structures are based on top-down or bottom-up strategies. Using spin-polarized density functional theory (DFT) combined with Monte Carlo simulations, the geometric stability, electronic structure and magnetic property of assembled 2D magnetic kagome lattices will be systematically studied in order to further understand the mechanism of magnetic coupling between two building blocks and the variation of magnetic moments with temperature. This study will extend the application of 2D materials in spintronic materials and stimulate an experimental effort to develop nanopatterning techniques for the synthesis of novel magnetic nanomaterials. The project combines spintronics, mathematical model, design of nanomaterials, and provides a method of the transition from mathematical model to real material.

基于数学模型二维Kagome点阵组装设计的新材料具有优良的磁性和机械性能。二维Kagome点阵可以看作是由正三角形按照两个三角形共用一个顶点的方式交错排列所形成的一种二维晶格结构，是设计磁性纳米材料的一个理想模型。本课题把具有铁磁性的纳米三角片或者平面小分子作为组装基元，基于二维Kagome点阵模型，采用自上而下和自下而上两种方法设计二维的轻质磁性纳米材料；采用自旋极化的密度泛函理论和Monte Carlo模拟方法系统地研究基于二维Kagome点阵组装材料的结构稳定性、磁耦合机理、电子结构，以便深入理解磁性基元之间的磁耦合机理以及磁矩随温度的变化特征，拓广二维纳米材料在自旋电子学中的应用，为新型磁性纳米材料的实验合成提供理论支撑。本项目融合了自旋电子学、数学模型、纳米材料的组装设计等多分支学科，实现数学模型到真实材料的转变，具有高度的交叉性。