中国物理B ›› 2018, Vol. 27 ›› Issue (8): 87305-087305.doi: 10.1088/1674-1056/27/8/087305

• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇    下一篇

Quantum spin Hall insulators in chemically functionalized As (110) and Sb (110) films

Xiahong Wang(王夏烘), Ping Li(李平), Zhao Ran(冉召), Weidong Luo(罗卫东)   

  1. 1 Key Laboratory of Artificial Structures and Quantum Control, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China;
    2 Institute of Natural Sciences, Shanghai Jiao Tong University, Shanghai 200240, China;
    3 Collaborative Innovation Center of Advanced Microstructures, Nanjing 210046, China
  • 收稿日期:2018-04-22 修回日期:2018-05-18 出版日期:2018-08-05 发布日期:2018-08-05
  • 通讯作者: Weidong Luo E-mail:wdluo@sjtu.edu.cn
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 11474197, U1632272, and 11521404).

Quantum spin Hall insulators in chemically functionalized As (110) and Sb (110) films

Xiahong Wang(王夏烘)1, Ping Li(李平)1, Zhao Ran(冉召)1, Weidong Luo(罗卫东)1,2,3   

  1. 1 Key Laboratory of Artificial Structures and Quantum Control, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China;
    2 Institute of Natural Sciences, Shanghai Jiao Tong University, Shanghai 200240, China;
    3 Collaborative Innovation Center of Advanced Microstructures, Nanjing 210046, China
  • Received:2018-04-22 Revised:2018-05-18 Online:2018-08-05 Published:2018-08-05
  • Contact: Weidong Luo E-mail:wdluo@sjtu.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 11474197, U1632272, and 11521404).

摘要: We propose a new type of quantum spin Hall (QSH) insulator in chemically functionalized As (110) and Sb (110) film. According to first-principles calculations, we find that metallic As (110) and Sb (110) films become QSH insulators after being chemically functionalized by hydrogen (H) or halogen (Cl and Br) atoms. The energy gaps of the functionalized films range from 0.121 eV to 0.304 eV, which are sufficiently large for practical applications at room temperature. The energy gaps originate from the spin-orbit coupling (SOC). The energy gap increases linearly with the increase of the SOC strength λ/λ0. The Z2 invariant and the penetration depth of the edge states are also calculated and studied for the functionalized films.

关键词: quantum spin Hall insulators, density functional theory (DFT), chemical functionalization, As (110) and Sb (110) film, Z2 topological invariants

Abstract: We propose a new type of quantum spin Hall (QSH) insulator in chemically functionalized As (110) and Sb (110) film. According to first-principles calculations, we find that metallic As (110) and Sb (110) films become QSH insulators after being chemically functionalized by hydrogen (H) or halogen (Cl and Br) atoms. The energy gaps of the functionalized films range from 0.121 eV to 0.304 eV, which are sufficiently large for practical applications at room temperature. The energy gaps originate from the spin-orbit coupling (SOC). The energy gap increases linearly with the increase of the SOC strength λ/λ0. The Z2 invariant and the penetration depth of the edge states are also calculated and studied for the functionalized films.

Key words: quantum spin Hall insulators, density functional theory (DFT), chemical functionalization, As (110) and Sb (110) film, Z2 topological invariants

中图分类号:  (Theory and modeling)

  • 73.43.Cd
73.43.-f (Quantum Hall effects) 73.20.-r (Electron states at surfaces and interfaces) 73.20.At (Surface states, band structure, electron density of states)