多体微扰和动力学平均场论中Fock交换的影响
Influence of Fock exchange in combined many-body perturbation and dynamical mean field theory
摘要：
在具有长程库仑相互作用的电子系统中，非定域Fock交换项具有带加宽效应。虽然这种影响包括在多体微扰理论和动力学平均场论的组合方案，它是不考虑在标准的扩展DMFT（EDMFT）计算。在这里，我们包括这两种方法中的瞬时项，并研究其对相图和动态屏蔽相互作用的影响。我们发现，以前提出的EDMFT和$GW$ +EDMFT的结果之间的最大偏差源自非本地Fock项，并且在强耦合极限的定量差异特别大。此外，我们表明，在$GW$ +EDMFT方法中获得的中等相互作用值的电荷有序相图是非常相似的预测由双玻色子方法，包括费米子玻色子或四点顶点。
英文摘要：
In electronic systems with long-range Coulomb interaction, the nonlocal Fock exchange term has a band-widening effect. While this effect is included in combined many-body perturbation theory and dynamical mean field theory schemes, it is not taken into account in standard extended DMFT (EDMFT) calculations. Here, we include this instantaneous term in both approaches and investigate its effect on the phase diagram and dynamically screened interaction. We show that the largest deviations between previously presented EDMFT and $GW$+EDMFT results originate from the nonlocal Fock term, and that the quantitative differences are especially large in the strong-coupling limit. Furthermore, we show that the charge-ordering phase diagram obtained in $GW$+EDMFT methods for moderate interaction values is very similar to the one predicted by dual boson methods that include the fermion-boson or four-point vertex.
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。
