English

Experimental verification of the "rainbow" trapping effect in plasmonic graded gratings

Optics 2015-05-18 v1

Abstract

We report the first experimental observation of trapped rainbow1 in graded metallic gratings2-4, designed to validate theoretical predictions for this new class of plasmonic structures. One-dimensional tapered gratings were fabricated and their surface dispersion properties tailored by varying the grating period and depth, whose dimensions were confirmed by atomic force microscopy. Reduced group velocities and the plasmonic bandgap were observed. Direct measurements on graded grating structures show that light of different wavelengths in the 500-700nm region is "trapped" at different positions along the grating, consistent with computer simulations, thus verifying the "rainbow" trapping effect. The trapped rainbow effect offers exciting pathways for optical information storage and optical delays in photonic circuits at ambient temperature.

Keywords

Cite

@article{arxiv.1003.4060,
  title  = {Experimental verification of the "rainbow" trapping effect in plasmonic graded gratings},
  author = {Qiaoqiang Gan and Yongkang Gao and Kyle Wagner and Dmitri V. Vezenov and Yujie J. Ding and Filbert J. Bartoli},
  journal= {arXiv preprint arXiv:1003.4060},
  year   = {2015}
}