Dornheim Tobias, Tolias Panagiotis, Moldabekov Zhandos A, Cangi Attila, Vorberger Jan
Center for Advanced Systems Understanding (CASUS), D-02826 Görlitz, Germany.
Space and Plasma Physics, Royal Institute of Technology (KTH), Stockholm SE-100 44, Sweden.
J Chem Phys. 2022 Jun 28;156(24):244113. doi: 10.1063/5.0097768.
The rigorous description of correlated quantum many-body systems constitutes one of the most challenging tasks in contemporary physics and related disciplines. In this context, a particularly useful tool is the concept of effective pair potentials that take into account the effects of the complex many-body medium consistently. In this work, we present extensive, highly accurate ab initio path integral Monte Carlo (PIMC) results for the effective interaction and the effective force between two electrons in the presence of the uniform electron gas. This gives us a direct insight into finite-size effects, thereby, opening up the possibility for novel domain decompositions and methodological advances. In addition, we present unassailable numerical proof for an effective attraction between two electrons under moderate coupling conditions, without the mediation of an underlying ionic structure. Finally, we compare our exact PIMC results to effective potentials from linear-response theory, and we demonstrate their usefulness for the description of the dynamic structure factor. All PIMC results are made freely available online and can be used as a thorough benchmark for new developments and approximations.
对相关量子多体系统进行严格描述是当代物理学及相关学科中最具挑战性的任务之一。在此背景下，一个特别有用的工具是有效对势的概念，它能始终如一地考虑复杂多体介质的影响。在这项工作中，我们给出了在均匀电子气存在的情况下，两个电子之间有效相互作用和有效力的广泛且高度精确的从头算路径积分蒙特卡罗（PIMC）结果。这使我们能直接洞察有限尺寸效应，从而为新颖的区域分解和方法学进展开辟了可能性。此外，我们给出了无可争议的数值证据，证明在适度耦合条件下，两个电子之间存在有效吸引，且无需底层离子结构的介导。最后，我们将精确的PIMC结果与线性响应理论中的有效势进行比较，并展示了它们在描述动态结构因子方面的有用性。所有PIMC结果都可在网上免费获取，并可作为新进展和近似方法的全面基准。
