Directly patterned substrate-free plasmonic 'nanograter' structures with unusual Fano resonances

Cui, A; Liu, Z; Li, J; Shen, T; Xia, X; Li, Z; Gong, Z; Li, H; Wang, B; Li, J; Yang, H; Li, W; Gu, C

Abstract

The application of three-dimensional (3D) plasmonic nanostructures as metamaterials,nano-antennas, and other devices faces challenges in producing metallic nanostructures with easily definable orientations, sophisticated shapes and smooth surfaces that are operational in the optical regime and beyond. Here, we demonstrate that complex 3D nanostructures can be readily
achieved with focused-ion-beam irradiation-induced folding and examine the optical characteristics of plasmonic “nanograter” structures that are composed of free-standing Au films.These 3D nanostructures exhibit interesting 3D hybridization in current flows and exhibit unusual and well-scalable Fano resonances at wavelengths ranging from 1.6 to 6.4 μm. Upon the introduction of liquids of various refractive indices to the structures, a strong dependence of the Fano resonance is observed, with spectral sensitivities of 1400 nm and 2,040 nm per refractive-index-unit (RIU) under figures of merit of 35.0 and 12.5, respectively, for low-order and high-order resonance in the near-infrared region. This work indicates the exciting, increasing relevance of similarly constructed 3D free standing nanostructures in the research and development of photonics and metamaterials.

Citation

Cui, A., Liu, Z., Li, J., Shen, T., Xia, X., Li, Z., …Gu, C. (2015). Directly patterned substrate-free plasmonic 'nanograter' structures with unusual Fano resonances. Light: Science & Applications (Print), 4, e308. https://doi.org/10.1038/lsa.2015.81

• Journal Article Type: Article
• Acceptance Date: Mar 24, 2015
• Online Publication Date: Jul 3, 2015
• Publication Date: Jul 3, 2015
• Deposit Date: Jun 17, 2015
• Publicly Available Date: Apr 5, 2016
• Journal: Light : Science & Applications (Nature Series)
• Print ISSN: 2095-5545
• Publisher: Springer Nature [academic journals on nature.com]
• Peer Reviewed: Peer Reviewed
• Volume: 4
• Pages: e308
• DOI: https://doi.org/10.1038/lsa.2015.81
• Publisher URL: http://dx.doi.org/10.1038/lsa.2015.81
• Related Public URLs: http://www.nature.com/lsa/index.html
• Additional Information: Funders : National Natural Science Foundation of China (NNSFC);Technical Talent Program of the Chinese Academy of Sciences; Grant Number: 91123004, 11104334, 51272278, 61390503, 11434017, 61475186 and 91023041