1. Controllable band structure and topological phase transition in two-dimensional hydrogenated arsenene
- Author
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Ping Li, Ya-ping Wang, Pei-ji Wang, Chang-wen Zhang, Miao-juan Ren, Feng Li, Wei-xiao Ji, Xinlian Chen, and Min Yuan
- Subjects
Physics ,Multidisciplinary ,Condensed matter physics ,Band gap ,Hash function ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Article ,Atomic orbital ,Quantum state ,Topological insulator ,0103 physical sciences ,Topological order ,010306 general physics ,0210 nano-technology ,Electronic band structure ,Quantum well - Abstract
Discovery of two-dimensional (2D) topological insulator such as group-V films initiates challenges in exploring exotic quantum states in low dimensions. Here, we perform first-principles calculations to study the geometric and electronic properties in 2D arsenene monolayer with hydrogenation (HAsH). We predict a new σ-type Dirac cone related to the px,y orbitals of As atoms in HAsH, dependent on in-plane tensile strain. Noticeably, the spin-orbit coupling (SOC) opens a quantum spin Hall (QSH) gap of 193 meV at the Dirac cone. A single pair of topologically protected helical edge states is established for the edges and its QSH phase is confirmed with topological invariant Z2 = 1. We also propose a 2D quantum well (QW) encapsulating HAsH with the h-BN sheet on each side, which harbors a nontrivial QSH state with the Dirac cone lying within the band gap of cladding BN substrate. These findings provide a promising innovative platform for QSH device design and fabrication operating at room temperature.
- Published
- 2016
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