发表机构
Brigham Young University（杨百翰大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究提出一种结合Onsager反应场的分子场理论方法，从磁对分布函数分析中提取交换参数，并在多种材料中验证其与文献值一致。
AI 中文摘要
确定磁交换相互作用对于理解材料的磁性行为至关重要。确定交换相互作用的标准方法是对单晶进行非弹性中子散射实验，以测量从长程有序的磁性基态出发的自旋波色散关系。然而，交换相互作用的影响并不仅限于有序态中的自旋波，它还支配着所有磁性状态下的磁性行为，包括持续存在于顺磁区域的短程自旋关联。过去已成功地从顺磁体的能量积分漫散射中子散射数据中恢复交换参数，这表明漫散射及其背后的短程磁关联富含信息。因此，磁对分布函数（mPDF）分析，它直接在实空间中探测短程磁关联，预计非常适合从关联顺磁体中提取交换参数。在这里，我们展示了一种稳健的分子场理论方法，该方法结合了Onsager反应场，用于从mPDF分析结果中确定交换参数。我们成功地将此方法应用于几种相关材料，恢复的交换相互作用值与文献值相当。
英文摘要
Determining magnetic exchange interactions is vital for understanding the magnetic behavior of materials. The standard method for exchange interaction determination involves performing inelastic neutron scattering experiments on single crystals to measure spin wave dispersions from a long-range-ordered magnetic ground state. However, the influence of exchange interactions is not limited exclusively to spin waves in ordered states, but also governs magnetic behavior in all magnetic states, including the short-range spin correlations that persist into the paramagnetic regime. Exchange parameters have been successfully recovered in the past from energy-integrated diffuse neutron scattering data from paramagnets, indicating that the diffuse scattering and underlying short-range magnetic correlations are rich in information. Consequently, magnetic pair distribution function (mPDF) analysis, which directly probes short-range magnetic correlations in real space, is expected to be well suited for extracting exchange parameters from correlated paramagnets. Here, we demonstrate a robust mean-field theory approach incorporating the Onsager reaction field for determination of exchange parameters from the results of mPDF analysis. We successfully apply this approach to several relevant materials to recover exchange interaction values comparable to literature values.
Comments12 Pages, 1 figure, 1 table
