论文标题
非赫森贝格磁相互作用对铁磁铁缺陷的影响
Effect of Non-Heisenberg Magnetic Interactions on Defects in Ferromagnetic Iron
论文作者
论文摘要
海森伯格汉密尔顿人的基本缺陷在其应用于BCC FE的背景下被强调，包括在建模晶格缺陷时引起的特定问题。使用磁力定理评估交换积分。在包含缺陷的大型模拟细胞中，对所有相互作用的原子磁矩成对计算双线性交换耦合常数，从而使磁能直接映射到Heisenberg Hamiltonian上并揭示其局限性。我们提供了一个简单的程序，可以从DFT计算中提取Landau参数，以构建Heisenberg-Landau Hamiltonian。我们定量地显示了Landau术语如何纠正交换 - 能源超表面，这对于对缺陷的能量和迁移障碍的准确评估至关重要。
Fundamental flaws in the Heisenberg Hamiltonian are highlighted in the context of its application to BCC Fe, including the particular issues arising when modelling lattice defects. Exchange integrals are evaluated using the magnetic force theorem. The bilinear exchange coupling constants are calculated for all the interacting pairs of atomic magnetic moments in large simulation cells containing defects, enabling a direct mapping of the magnetic energy onto the Heisenberg Hamiltonian and revealing its limitations. We provide a simple procedure for extracting the Landau parameters from DFT calculations, to construct a Heisenberg-Landau Hamiltonian. We quantitatively show how the Landau terms correct the exchange-energy hypersurface, which is essential for the accurate evaluation of energies and migration barriers of defects.
