对称性投射集群平均场理论应用于自旋系统
Athanasios Papastathopoulos-Katsaros1, Thomas M Henderson1,2, Gustavo E Scuseria1,2
1Department of Chemistry, Rice University, Houston, Texas 77005, USA.
The Journal of chemical physics
|August 23, 2023
概括
我们开发了新的方法,通用集群平均场 (GcMF) 和Sz旋转投影通用集群平均场 (SzGcMF),以更好地描述强烈相关的旋转系统. 这些方法提高了海森堡模型中集群间相关性的理解.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 量子多体理论 量子多体理论
- 计算物理 计算物理
背景情况:
- 集群平均场理论使用因子化的集群波函数近似地基状态.
- 之前的不受限制的集群平均场方法在每个集群中保持了Sz对称性.
- 强烈相关的旋转系统对准确的理论描述提出了重大挑战.
研究的目的:
- 介绍概括的集群平均场 (GcMF) 理论,放松每个集群的 Sz 对称约束.
- 通过恢复全球 Sz 对称性来开发 Sz 旋转投影的泛化集群平均场 (SzGcMF).
- 改进在强烈相关的旋转系统中对集群间相关性的核算.
主要方法:
- 开发了通用的集群平均场 (GcMF) 理论,允许集群访问所有 Sz 部门.
- 实施了Sz旋转投影以恢复全球Sz对称性,形成SzGcMF.
- 将GcMF和SzGcMF应用于基准1D,准2D和2D J1-J2和XXZ海森堡模型.
主要成果:
- GcMF和SzGcMF方法提供了海森堡格子的定性和半定量描述.
- 新的方法成功考虑了集群间的相关性.
- 与以前的集群平均场方法相比,证明了更好的准确性.
结论:
- GcMF和SzGcMF是研究强烈相关的旋转系统的宝贵工具.
- 这些方法为集群间的相关性提供了更好的见解.
- 开发的理论可以作为未来该领域研究的有用参考.
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