论文标题
光激发的动力内核
Dynamical Kernels for Optical Excitations
论文作者
论文摘要
We discuss the physical properties and accuracy of three distinct dynamical (ie, frequency-dependent) kernels for the computation of optical excitations within linear response theory: i) an a priori built kernel inspired by the dressed time-dependent density-functional theory (TDDFT) kernel proposed by Maitra and coworkers, ii) the dynamical kernel stemming from the Bethe-Salpeter equation (BSE) formalism derived最初由strinati和iii）Yang及其同事得出的二阶BSE内核。本文的主要收入消息是，由于其频率依赖性的性质，可以与高阶激发相关的其他激发（例如臭名昭著的双重激发），这是动态数量的未欣赏特征，因此动态内核可以提供。我们还为每个内核分析了源自内核的近似性质的虚假激发的出现，Romaniello首先证明了这一点。使用简单的两级模型，考虑了价值，电荷转移和Rydberg激发态的原型示例。
We discuss the physical properties and accuracy of three distinct dynamical (ie, frequency-dependent) kernels for the computation of optical excitations within linear response theory: i) an a priori built kernel inspired by the dressed time-dependent density-functional theory (TDDFT) kernel proposed by Maitra and coworkers, ii) the dynamical kernel stemming from the Bethe-Salpeter equation (BSE) formalism derived originally by Strinati , and iii) the second-order BSE kernel derived by Yang and coworkers . The principal take-home message of the present paper is that dynamical kernels can provide, thanks to their frequency-dependent nature, additional excitations that can be associated to higher-order excitations (such as the infamous double excitations), an unappreciated feature of dynamical quantities. We also analyze, for each kernel, the appearance of spurious excitations originating from the approximate nature of the kernels, as first evidenced by Romaniello. Using a simple two-level model, prototypical examples of valence, charge-transfer, and Rydberg excited states are considered.
