English

Visualizing plasmon coupling in closely-spaced chains of Ag nanoparticles by electron energy loss spectroscopy

Mesoscale and Nanoscale Physics 2012-02-14 v1 Materials Science

Abstract

Anisotropic plasmon coupling in closely-spaced chains of Ag nanoparticles was visualized using the electron energy loss spectroscopy in a scanning transmission electron microscope. For dimers as the simplest chain, mapping the plasmon excitations with nanometers' spatial resolution and 0.27 eV energy resolution intuitively identified two coupling plasmons. The in-phase mode redshifted from the ultraviolet region as the inter-particle spacing was reduced, reaching the visible range at 2.7 eV. Calculations based on the discrete dipole approximation confirmed its optical activeness, where the longitudinal direction was constructed as the path for light transportation. Two coupling paths were then observed in an inflexed 4-particle chain.

Keywords

Cite

@article{arxiv.1202.2610,
  title  = {Visualizing plasmon coupling in closely-spaced chains of Ag nanoparticles by electron energy loss spectroscopy},
  author = {Fengqi Song and Tingyu Wang and Xuefeng Wang and Changhui Xu and Longbing He and Jianguo Wan and Chris Van Haesendonck and Simon P. Ringer and Min Han and Zongwen Liu and Guanghou Wang},
  journal= {arXiv preprint arXiv:1202.2610},
  year   = {2012}
}