›› 2014, Vol. 23 ›› Issue (10): 107807-107807.doi: 10.1088/1674-1056/23/10/107807

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

Terahertz plasmon and surface-plasmon modes in cylindrical metallic nanowires

吴平a, 徐文a b, 李龙龙a, 卢铁城c, 吴卫东d   

  1. a Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, China;
    b Department of Physics, Yunnan University, Kunming 650091, China;
    c Department of Physics, Sichuan University, Chengdu 610064, China;
    d Institute of Applied Electronics, China Academy of Engineering Physics, Mianyang 621900, China
  • 收稿日期:2014-02-16 修回日期:2014-04-22 出版日期:2014-10-15 发布日期:2014-10-15
  • 基金资助:
    Project supported by the Funds from the Ministry of Science and Technology of China (Grant No. 2011YQ130018), the Funds from the Department of Science and Technology of Yunnan Province, the Open Research Fund Program of the State Key Laboratory of Low-Dimensional Quantum Physics (Grant No. KF201303), the Joint Research Fund from Sichuan University and China Academy of Engineering Physics, and the Funds from the Chinese Academy of Sciences (Grant No. YZ201223).

Terahertz plasmon and surface-plasmon modes in cylindrical metallic nanowires

Wu Ping (吴平)a, Xu Wen (徐文)a b, Li Long-Long (李龙龙)a, Lu Tie-Cheng (卢铁城)c, Wu Wei-Dong (吴卫东)d   

  1. a Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, China;
    b Department of Physics, Yunnan University, Kunming 650091, China;
    c Department of Physics, Sichuan University, Chengdu 610064, China;
    d Institute of Applied Electronics, China Academy of Engineering Physics, Mianyang 621900, China
  • Received:2014-02-16 Revised:2014-04-22 Online:2014-10-15 Published:2014-10-15
  • Contact: Xu Wen E-mail:wenxu_issp@aliyun.com
  • About author:78.67.Uh; 73.20.Mf
  • Supported by:
    Project supported by the Funds from the Ministry of Science and Technology of China (Grant No. 2011YQ130018), the Funds from the Department of Science and Technology of Yunnan Province, the Open Research Fund Program of the State Key Laboratory of Low-Dimensional Quantum Physics (Grant No. KF201303), the Joint Research Fund from Sichuan University and China Academy of Engineering Physics, and the Funds from the Chinese Academy of Sciences (Grant No. YZ201223).

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摘要： We present a theoretical study on collective excitation modes associated with plasmon and surface-plasmon oscillations in cylindrical metallic nanowires. Based on a two-subband model, the dynamical dielectric function matrix is derived under the random-phase approximation. An optic-like branch and an acoustic-like branch, which are free of Landau damping, are observed for both plasmon and surface-plasmon modes. Interestingly, for surface-plasmon modes, we find that two branches of the dispersion relation curves converge at a wavevector qz=qmax beyond which no surface-plasmon mode exists. Moreover, we examine the dependence of these excitation modes on sample parameters such as the radius of the nanowires. It is found that in metallic nanowires realized by state-of-the-art nanotechnology the intra-and inter-subband plasmon and surface-plasmon frequencies are in the terahertz bandwidth. The frequency of the optic-like modes decreases with increasing radius of the nanowires, whereas that of the acoustic-like modes is not sensitive to the variation of the radius. This study is pertinent to the application of metallic nanowires as frequency-tunable terahertz plasmonic devices.

关键词: metallic nanowires, collective excitations, terahertz

Abstract: We present a theoretical study on collective excitation modes associated with plasmon and surface-plasmon oscillations in cylindrical metallic nanowires. Based on a two-subband model, the dynamical dielectric function matrix is derived under the random-phase approximation. An optic-like branch and an acoustic-like branch, which are free of Landau damping, are observed for both plasmon and surface-plasmon modes. Interestingly, for surface-plasmon modes, we find that two branches of the dispersion relation curves converge at a wavevector qz=qmax beyond which no surface-plasmon mode exists. Moreover, we examine the dependence of these excitation modes on sample parameters such as the radius of the nanowires. It is found that in metallic nanowires realized by state-of-the-art nanotechnology the intra-and inter-subband plasmon and surface-plasmon frequencies are in the terahertz bandwidth. The frequency of the optic-like modes decreases with increasing radius of the nanowires, whereas that of the acoustic-like modes is not sensitive to the variation of the radius. This study is pertinent to the application of metallic nanowires as frequency-tunable terahertz plasmonic devices.

Key words: metallic nanowires, collective excitations, terahertz

中图分类号:  (Nanowires)

  • 78.67.Uh
73.20.Mf (Collective excitations (including excitons, polarons, plasmons and other charge-density excitations))