中国物理B ›› 2015, Vol. 24 ›› Issue (7): 77301-077301.doi: 10.1088/1674-1056/24/7/077301

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

Au and Ti induced charge redistributions on monolayer WS2

朱会丽a, 杨伟煌b, 吴雅苹c, 林伟c, 康俊勇c, 周昌杰a   

  1. a Department of Physics, School of Science, Jimei University, Xiamen 361021, China;
    b Division of Physics and Applied Physics, School of Physical and Mathematical Science, Nanyang Technological University, 637371 Singapore;
    c Department of Physics, Fujian Key Laboratory of Semiconductor Materials and Applications, Xiamen University, Xiamen 361005, China
  • 收稿日期:2014-10-30 修回日期:2015-02-09 出版日期:2015-07-05 发布日期:2015-07-05
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 91321102, 11304257, and 61227009), the Natural Science Foundation of Fujian Province, China (Grant Nos. 2011J05006, 2009J05149, and 2014J01026), the Foundation from Department of Education of Fujian Province, China (Grant No. JA09146), Huang Hui Zhen Foundation of Jimei University, China (Grant No. ZC2010014), and the Scientific Research Foundation of Jimei University, China (Grant Nos. ZQ2011008 and ZQ2009004).

Au and Ti induced charge redistributions on monolayer WS2

Zhu Hui-Li (朱会丽)a, Yang Wei-Huang (杨伟煌)b, Wu Ya-Ping (吴雅苹)c, Lin Wei (林伟)c, Kang Jun-Yong (康俊勇)c, Zhou Chang-Jie (周昌杰)a   

  1. a Department of Physics, School of Science, Jimei University, Xiamen 361021, China;
    b Division of Physics and Applied Physics, School of Physical and Mathematical Science, Nanyang Technological University, 637371 Singapore;
    c Department of Physics, Fujian Key Laboratory of Semiconductor Materials and Applications, Xiamen University, Xiamen 361005, China
  • Received:2014-10-30 Revised:2015-02-09 Online:2015-07-05 Published:2015-07-05
  • Contact: Zhou Chang-Jie E-mail:zhoucj@jmu.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 91321102, 11304257, and 61227009), the Natural Science Foundation of Fujian Province, China (Grant Nos. 2011J05006, 2009J05149, and 2014J01026), the Foundation from Department of Education of Fujian Province, China (Grant No. JA09146), Huang Hui Zhen Foundation of Jimei University, China (Grant No. ZC2010014), and the Scientific Research Foundation of Jimei University, China (Grant Nos. ZQ2011008 and ZQ2009004).

摘要: By using the first-principles calculations, structural and electronic properties of Au and Ti adsorbed WS2 monolayers are studied systematically. For Au-adsorbed WS2, metallic interface states are induced in the middle of the band gap across the Fermi level. These interface states origin mainly from the Au-6s states. As to the Ti adsorbed WS2, some delocalized interface states appear and follow the bottom of conduction band. The Fermi level arises into the conduction band and leads to the n-type conducting behavior. The n-type interface states are found mainly come from the Ti-3d and W-5d states due to the strong Ti–S hybridization. The related partial charge densities between Ti and S atoms are much higher and increased by an order of magnitude as compared with that of Au-adsorbed WS2. Therefore, the electron transport across the Ti-adsorbed WS2 system is mainly by the resonant transport, which would further enhances the electronic transparency when monolayer WS2 contacts with metal Ti. These investigations are of significant importance in understanding the electronic properties of metal atom adsorption on monolayer WS2 and offer valuable references for the design and fabrication of 2D nanodevices.

关键词: WS2, transition metal dichalcogenides, two-dimensional materials, first-principles calculations

Abstract: By using the first-principles calculations, structural and electronic properties of Au and Ti adsorbed WS2 monolayers are studied systematically. For Au-adsorbed WS2, metallic interface states are induced in the middle of the band gap across the Fermi level. These interface states origin mainly from the Au-6s states. As to the Ti adsorbed WS2, some delocalized interface states appear and follow the bottom of conduction band. The Fermi level arises into the conduction band and leads to the n-type conducting behavior. The n-type interface states are found mainly come from the Ti-3d and W-5d states due to the strong Ti–S hybridization. The related partial charge densities between Ti and S atoms are much higher and increased by an order of magnitude as compared with that of Au-adsorbed WS2. Therefore, the electron transport across the Ti-adsorbed WS2 system is mainly by the resonant transport, which would further enhances the electronic transparency when monolayer WS2 contacts with metal Ti. These investigations are of significant importance in understanding the electronic properties of metal atom adsorption on monolayer WS2 and offer valuable references for the design and fabrication of 2D nanodevices.

Key words: WS2, transition metal dichalcogenides, two-dimensional materials, first-principles calculations

中图分类号:  (Surface states, band structure, electron density of states)

  • 73.20.At
73.22.-f (Electronic structure of nanoscale materials and related systems) 81.05.Hd (Other semiconductors) 68.43.Bc (Ab initio calculations of adsorbate structure and reactions)