Institute for Theoretical Physics, TU Wien, Wiedner Hauptstraße 8-10/136, 1040 Vienna, Austria.
Phys Rev Lett. 2019 Oct 11;123(15):156401. doi: 10.1103/PhysRevLett.123.156401.
We present a diagrammatic decomposition of the transition pair correlation function for the uniform electron gas. We demonstrate explicitly that ring and ladder diagrams are dual counterparts that capture significant long- and short-ranged interelectronic correlation effects, respectively. Our findings help to guide the further development of approximate many-electron theories and reveal that the contribution of the ladder diagrams to the electronic correlation energy can be approximated in an effective manner using second-order perturbation theory. We employ the latter approximation to reduce the computational cost of coupled cluster theory calculations for insulators and semiconductors by 2 orders of magnitude without compromising accuracy.
我们给出了均匀电子气的跃迁对关联函数的一个图示分解。我们明确地证明了，环图和梯图是对偶的，分别捕捉了显著的长程和短程电子相关效应。我们的发现有助于指导进一步发展近似多电子理论，并揭示了用二阶微扰理论可以有效地近似梯图对电子相关能的贡献。我们采用后一种近似方法，将绝缘体和半导体的耦合簇理论计算的计算成本降低了 2 个数量级，而精度不受影响。
