中国物理B ›› 2017, Vol. 26 ›› Issue (10): 108101-108101.doi: 10.1088/1674-1056/26/10/108101

• INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY • 上一篇    下一篇

Germanene nanomeshes:Cooperative effects of degenerate perturbation and uniaxial strain on tuning bandgap

Yan Su(苏燕), Xinyu Fan(范新宇)   

  1. Department of Physics, University of Ji'nan, Ji'nan 250022, China
  • 收稿日期:2017-05-27 修回日期:2017-06-30 出版日期:2017-10-05 发布日期:2017-10-05
  • 通讯作者: Xinyu Fan E-mail:xyfan_ujn@163.com
  • 基金资助:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 11374128 and 11674129) and partially supported by the Science and Technology Program of University of Jinan (Grant No. XKY1705).

Germanene nanomeshes:Cooperative effects of degenerate perturbation and uniaxial strain on tuning bandgap

Yan Su(苏燕), Xinyu Fan(范新宇)   

  1. Department of Physics, University of Ji'nan, Ji'nan 250022, China
  • Received:2017-05-27 Revised:2017-06-30 Online:2017-10-05 Published:2017-10-05
  • Contact: Xinyu Fan E-mail:xyfan_ujn@163.com
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 11374128 and 11674129) and partially supported by the Science and Technology Program of University of Jinan (Grant No. XKY1705).

摘要:

Based on the detailed first-principles calculations, we have carefully investigated the defect induced band splitting and its combination with Dirac cone move in bandgap opening. The uniaxial strain can split the π -like bands into πa and πz bands with energy interval Estrain to shift the Dirac cone. Also, the inversion symmetry preserved antidot can split πa (πz) into πa1 and πa2 (πz1 and πz2) bands with energy interval Edefect to open bandgap in the nanomesh with Γ as four-fold degenerate Dirac point according to the band-folding analysis. Though the Edefect would keep almost unaffected, the Estrain would be increased by enhancing the uniaxial strain to continuously tune the gap width. Then the bandgap can be reversibly switched on/off. Our studies of the inversion symmetry preserved nanomesh show distinct difference in bandgap opening mechanism as compared to the one by breaking the sublattice equivalence in the (GaAs)6 nanoflake patterned nanomesh. Here, the π-band gap remains almost unchanged against strain enhancing.

关键词: first-principles calculation, novel two-dimensional nanostructure, bandgap engineering

Abstract:

Based on the detailed first-principles calculations, we have carefully investigated the defect induced band splitting and its combination with Dirac cone move in bandgap opening. The uniaxial strain can split the π -like bands into πa and πz bands with energy interval Estrain to shift the Dirac cone. Also, the inversion symmetry preserved antidot can split πa (πz) into πa1 and πa2 (πz1 and πz2) bands with energy interval Edefect to open bandgap in the nanomesh with Γ as four-fold degenerate Dirac point according to the band-folding analysis. Though the Edefect would keep almost unaffected, the Estrain would be increased by enhancing the uniaxial strain to continuously tune the gap width. Then the bandgap can be reversibly switched on/off. Our studies of the inversion symmetry preserved nanomesh show distinct difference in bandgap opening mechanism as compared to the one by breaking the sublattice equivalence in the (GaAs)6 nanoflake patterned nanomesh. Here, the π-band gap remains almost unchanged against strain enhancing.

Key words: first-principles calculation, novel two-dimensional nanostructure, bandgap engineering

中图分类号:  (New materials: theory, design, and fabrication)

  • 81.05.Zx
81.05.Rm (Porous materials; granular materials) 81.05.ue (Graphene)