哈伯德U在高压下对金属进行的第一原理计算
Logan A Burnett1, Matthew P Clay1, Yogesh K Vohra1
1Department of Physics, University of Alabama at Birmingham, Birmingham, AL 35294, United States of America.
概括
我们计算了高压下的 (Tb) 金属的哈伯德U相互作用. 包括这种相互作用显著改善了稀土材料及其磁性质的建模.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学是一种材料科学.
- 计算材料科学 计算材料科学
背景情况:
- 准确的对相关稀土材料如 (Tb) 的建模对于理解它们的特性至关重要.
- 密度函数理论 (DFT) 是一种常见的方法,但通常需要对强烈相关的系统进行校正.
研究的目的:
- 计算在现场的哈伯德相互作用 (U) 对元素 (Tb) 金属在广泛的压力范围 (0-65 GPa).
- 在DFT+U框架内使用计算的U值来研究Tb在压力下的磁性特性.
- 评估哈伯德U校正对结核病建模准确性和效率的影响.
主要方法:
- 使用密度函数理论 (DFT) 结合线性响应方法来计算哈伯德U.
- 采用DFT+U方法研究Tb的磁性特性,使用第一原则的U值和实验性晶体结构.
- 检查了Tb的各种高压相,包括六角密封 (hcp),α-Samarium (α-Sm) 和双六角密封 (dhcp).
主要成果:
- 成功计算了Hubbard的第一原则U值,用于从0到65GPa的金属.
- 计算显示,高压Tb阶段的最低能量磁态与实验磁顺序向量保持一致.
- 证明将哈巴德U校正纳入其中显著提高了对相关稀土材料建模的准确性和效率.
结论:
- 计算的哈伯德U值对于在极端压力下对的精确DFT+U研究至关重要.
- 这项工作证实了哈伯德对稀土磁场的U校正的重要性.
- 为先进的量子多体技术提供了关键的U数据,用于在高压下研究.
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