准粒子
拓扑绝缘体
密度泛函理论
电子结构
材料科学
凝聚态物理
半金属
费米面
电子能带结构
价(化学)
物理
结晶学
带隙
量子力学
超导电性
化学
作者
Dmitrii Nabok,Murat Taş,S. Kusaka,Engin Durgun,Christoph Friedrich,Gustav Bihlmayer,Stefan Blügel,Toru Hirahara,Irene Aguilera
出处
期刊:Physical Review Materials
[American Physical Society]
日期:2022-03-23
卷期号:6 (3)
被引量:5
标识
DOI:10.1103/physrevmaterials.6.034204
摘要
We present a combined theoretical and experimental study of the electronic structure of stoichiometric ${\mathrm{Bi}}_{4}{\mathrm{Te}}_{3}$, a natural superlattice of alternating ${\mathrm{Bi}}_{2}{\mathrm{Te}}_{3}$ quintuple layers and Bi bilayers. In contrast to the related semiconducting compounds ${\mathrm{Bi}}_{2}{\mathrm{Te}}_{3}$ and ${\mathrm{Bi}}_{1}{\mathrm{Te}}_{1}$, density functional theory predicts ${\mathrm{Bi}}_{4}{\mathrm{Te}}_{3}$ is a semimetal. In this work, we compute the quasiparticle electronic structure of ${\mathrm{Bi}}_{4}{\mathrm{Te}}_{3}$ in the framework of the $GW$ approximation within many-body perturbation theory. The quasiparticle corrections are found to modify the dispersion of the valence and conduction bands in the vicinity of the Fermi energy, leading to the opening of a small indirect band gap. Based on the analysis of the eigenstates, ${\mathrm{Bi}}_{4}{\mathrm{Te}}_{3}$ is classified as a dual topological insulator with bulk topological invariants ${\mathbb{Z}}_{2} (1;111)$ and magnetic mirror Chern number ${n}_{M}=1$. The bulk $GW$ results are used to build a Wannier-function-based tight-binding Hamiltonian that is further applied to study the electronic properties of the (111) surface. The comparison with our angle-resolved photoemission measurements shows excellent agreement between the computed and measured surface states and indicates the dual topological nature of ${\mathrm{Bi}}_{4}{\mathrm{Te}}_{3}$.
科研通智能强力驱动
Strongly Powered by AbleSci AI