作者：M. Arruabarrena A. Leonardo A. Ayuela
时间依赖密度泛函理论（TDDFT）目前被认为是计算固体光学财产的多体微扰理论（MBPT）的一种廉价而有效的替代方法。在线性响应形式下，光学吸收光谱与实验以及激子结合能的直接测定结果非常一致。然而，被称为长程校正（LRC）核的交换相关核族，能够正确地捕获激子特征，很难同时产生良好的光谱和准确的激子结合能。最近，混合TDDFT方法部分克服了这种差异。我们表明，关键在于对长程库仑奇异项的数值处理。我们仔细研究了这个术语的影响，包括在纯TDDFT和使用Wigner-Seitz截断内核的混合方法中。我们发现计算这个术语在技术上
Time-Dependent Density Functional Theory (TDDFT) has been currentlyestablished as a computationally cheaper, yet effective, alternative to theMany-Body Perturbation Theory (MBPT) for calculating the optical properties ofsolids. Within the Linear Response formalism, the optical absorption spectraare in good agreement with experiments, as well as the direct determination ofthe exciton binding energies. However, the family of exchange-correlationkernels known as long-range corrected (LRC) kernels that correctly captureexcitonic features have difficulties simultaneously producing good-lookingspectra and accurate exciton binding energies. More recently, this discrepancyhas been partially overcome by a hybrid-TDDFT approach. We show that the keyresides in the numerical treatment of the long-range Coulomb singular term. Wecarefully study the effect of this term, both in the pure-TDDFT and hybridapproach using a Wigner-Seitz truncated kernel. We find that computing thisterm presents technical difficulties that are hard to overcome in bothapproaches, and that points to the need for a better description of theelectron-hole interaction.
论文链接：http://arxiv.org/pdf/2303.13389v1
更多计算机论文：http://cspaper.cn/