A finite electric-field approach to evaluate the vertex correction for the screened Coulomb interaction in the quasiparticle self-consistent GW method

التفاصيل البيبلوغرافية
العنوان: A finite electric-field approach to evaluate the vertex correction for the screened Coulomb interaction in the quasiparticle self-consistent GW method
المؤلفون: Sakakibara, Hirofumi, Kotani, Takao, Obata, Masao, Oda, Tatsuki
المصدر: Phys. Rev. B 101, 205120 (2020)
سنة النشر: 2019
المجموعة: Condensed Matter
مصطلحات موضوعية: Condensed Matter - Strongly Correlated Electrons, Condensed Matter - Materials Science
الوصف: We apply the quasiparticle self-consistent GW method (QSGW) to slab models of ionic materials, LiF, KF, NaCl, MgO, and CaO, under electric field. Then we obtain the optical dielectric constants E(Slab) from the differences of the slopes of the electrostatic potential in the bulk and vacuum regions. Calculated E(Slab) show very good agreements with experiments. For example, we have E(Slab)=2.91 for MgO, in agreement with the experimental value E(Experiment)=2.96. This is in contrast to E(RPA)=2.37, which is calculated in the random-phase approximation for the bulk MgO in QSGW. After we explain the difference between the quasiparticle-based perturbation theory and the Greens function based perturbation theory, we interpret the large difference E(Slab)-E(RPA)=2.91-2.37 as the contribution from the vertex correction of the proper polarization which determines the screened Coulomb interaction W. Our result encourages the theoretical development of self-consistent G0W approximation along the line of QSGW self-consistency, as was performed by Shishkin, Marsman and Kresse [Phys. Rev. Lett. 99, 246403(2007)].
Comment: 2 figures
نوع الوثيقة: Working Paper
DOI: 10.1103/PhysRevB.101.205120
URL الوصول: http://arxiv.org/abs/1909.12616
رقم الأكسشن: edsarx.1909.12616
قاعدة البيانات: arXiv
الوصف
DOI:10.1103/PhysRevB.101.205120