@article{oai:repository.lib.tottori-u.ac.jp:00007331,
 author = {Sakakibara, Hirofumi and Kotani, Takao and Obata, Masao and Oda, Tatsuki},
 journal = {Physical review. Third series. B, Condensed matter and materials physics, Physical review. Third series. B, Condensed matter and materials physics},
 month = {May},
 note = {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 ε∞(Slab) from the differences of the slopes of the electrostatic potential in the bulk and vacuum regions. Calculated ε∞(Slab) show very good agreement with experiments. For example, we have ε∞(Slab)=2.91 for MgO, in agreement with the experimental value ε∞(Experiment)=2.96. This is in contrast to ε∞(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 Green's-function-based perturbation theory, we interpret the large difference ε∞(Slab)−ε∞(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 the 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)].},
 title = {Finite electric-field approach to evaluate the vertex correction for the screened Coulomb interaction in the quasiparticle self-consistent GW method},
 volume = {101},
 year = {2020},
 yomi = {サカキバラ, ヒロフミ and コタニ, タカオ}
}