强局部相关性和集体涨落的统一方法：消除自旋通道中的发散
A Unified Approach to Strong Local Correlations and Collective Fluctuations: Eliminating Divergence in the Spin Channel
AI总结：
本文提出涨落动力学平均场理论（fDMFT），通过引入集体涨落来解决DMFT中自旋通道发散问题，并在近半满Hubbard模型中展现更优性能。
摘要：
动力学平均场理论（DMFT）通过将晶格映射到自洽的有效杂质模型上，为相关晶格系统提供了最优的局部近似。为弥补长程相关性的缺失，我们提出了一种新的扩展方法，称为涨落动力学平均场理论（fDMFT）。该方法通过功能积分在不同站点之间引入辅助杂质模型的集体涨落。技术上，该方法涉及在自洽的经典场应用于晶格时，在网格上获得一组DMFT解。虽然结果原则上可以通过图论方法改进，但我们发现该理论的最小版本已经能产生准确的结果，最低阶图论修正仅提供微小改进。基于我们涨落局部场概念的这一一致框架，相较于其他已知的DMFT图论扩展，在近半满Hubbard模型中表现出更优越的性能。
英文摘要：
Dynamical mean-field theory (DMFT) provides an optimal local approximation for correlated lattice systems by mapping the lattice onto a self-consistent effective impurity model. To account for the missing long-range correlations, we propose a novel extended approach, which we term fluctuating dynamical mean-field theory (fDMFT). It incorporates collective fluctuations of auxiliary impurity models across different sites via functional integration. Technically, this method involves obtaining a family of DMFT solutions on a grid for a self-consistent auxiliary classical field applied to the lattice. While the result can, in principle, be improved diagrammatically, we find that the minimal version of the theory already yields accurate results, with lowest-order diagrammatic corrections offering only minor improvements. This consistent framework, based on our fluctuating local field concept, demonstrates superior performance for the nearly half-filled Hubbard model compared to other known diagrammatic extensions of DMFT.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
