2020/12/17(Thu) 11:00 -12:00 五樓第一會議室 5F, 1st Meeting Room
Title
密度泛函理論的應用：從單電子圖像到多體物理
Applications of density functional theory: from single-particle picture to many-body physics
Speaker
李啟正助理教授 (淡江大學物理學系) Dr. Chi-Cheng Lee (Department of Physics, Tamkang University)Abstract
First-principles calculations based on density functional theory have been widely performed to understand and predict abundant physical properties of condensed matter. In this talk, the basic idea of density functional theory will be first introduced for highlighting three important ingredients: Kohn-Sham orbitals, the many-body charge density, and the many-body total energy. I will then discuss two issues based on the studies of Kohn-Sham orbitals, namely, the discovery of Weyl fermions in TaAs and the emergence of nearly flat bands in the two-dimensional Ge layer on ZrB2(0001). For the many-body charge density, the surface-assisted orbital order in CeCoIn5 will been discussed. Finally, I will address the absolute values of core-level binding energy for several materials, where the many-body total energies are needed to reproduce the experimentally observed XPS spectra.
Language
演講語言 (Language): in Mandarin