AI 中文总结
该研究从代数图构造（ADC）扩展版本推导出多通道戴森方程（MCDE），将其应用于一维周期性哈伯德模型，发现其在谱强度分布的准粒子峰和卫星峰处理上优于ADC(2)。
AI 中文摘要
多通道戴森方程（MCDE）是Riva等人2023年发表于《物理评论快报》第131卷第216401篇的新近似方案，用于计算多体系统中的单体格林函数。本文通过从代数图构造（ADC）截断方案的扩展版本中推导出该方案，进一步阐明了其物理内涵，证明MCDE近似介于动力学自能的ADC(2)和ADC(3)截断之间。基于此，研究将MCDE近似应用于具有4、6、8个格点的一维周期性哈伯德模型，结果显示其在谱强度分布的准粒子峰和卫星峰处理上均优于ADC(2)。
英文摘要
The multichannel Dyson equation (MCDE) was recently introduced as a new approximation scheme to compute the one-body Green function in many-body systems, as reported by Riva et al. in Physical Review Letters, volume 131, article 216401, published in 2023. The physical content of this novel approximation scheme is further clarified by recovering it from an extended version of the algebraic diagrammatic construction (ADC) truncation scheme. It is thus demonstrated that the MCDE approximation lies in between the so-called ADC(2) and ADC(3) truncations of the dynamical self energy. Building on this clarification, the MCDE approximation is tested on the periodic one-dimensional Hubbard model with 4, 6, and 8 site lattices and shown to deliver an improved treatment over ADC(2) of both the quasiparticle peaks and the so-called satellites in the spectral strength distribution.
