中国物理B ›› 2011, Vol. 20 ›› Issue (9): 97105-097105.doi: 10.1088/1674-1056/20/9/097105

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

A time-dependent density functional theory investigation of plasmon resonances of linear Au atomic chains

刘丹丹, 张红   

  1. College of Physical Science and Technology, Sichuan University, Chengdu 610065, China
  • 收稿日期:2011-04-01 修回日期:2011-04-27 出版日期:2011-09-15 发布日期:2011-09-15

A time-dependent density functional theory investigation of plasmon resonances of linear Au atomic chains

Liu Dan-Dan(刘丹丹) and Zhang Hong(张红)   

  1. College of Physical Science and Technology, Sichuan University, Chengdu 610065, China
  • Received:2011-04-01 Revised:2011-04-27 Online:2011-09-15 Published:2011-09-15

摘要: We report theoretical studies on the plasmon resonances in linear Au atomic chains by using ab initio time-dependent density functional theory. The dipole responses are investigated each as a function of chain length. They converge into a single resonance in the longitudinal mode but split into two transverse modes. As the chain length increases, the longitudinal plasmon mode is redshifted in energy while the transverse modes shift in the opposite direction (blueshifts). In addition, the energy gap between the two transverse modes reduces with chain length increasing. We find that there are unique characteristics, different from those of other metallic chains. These characteristics are crucial to atomic-scale engineering of single-molecule sensing, optical spectroscopy, and so on.

Abstract: We report theoretical studies on the plasmon resonances in linear Au atomic chains by using ab initio time-dependent density functional theory. The dipole responses are investigated each as a function of chain length. They converge into a single resonance in the longitudinal mode but split into two transverse modes. As the chain length increases, the longitudinal plasmon mode is redshifted in energy while the transverse modes shift in the opposite direction (blueshifts). In addition, the energy gap between the two transverse modes reduces with chain length increasing. We find that there are unique characteristics, different from those of other metallic chains. These characteristics are crucial to atomic-scale engineering of single-molecule sensing, optical spectroscopy, and so on.

Key words: plasmon resonance, time-dependent density functional theory, longitudinal plasmon mode, transverse plasmon mode

中图分类号:  (Exchange, correlation, dielectric and magnetic response functions, plasmons)

  • 71.45.Gm
72.15.Nj (Collective modes (e.g., in one-dimensional conductors)) 73.20.Mf (Collective excitations (including excitons, polarons, plasmons and other charge-density excitations))