Journal article
Plasmon resonances of Ag capped Si nanopillars fabricated using mask-less lithography
Department of Micro- and Nanotechnology, Technical University of Denmark1
Nanoprobes, Department of Micro- and Nanotechnology, Technical University of Denmark2
Department of Photonics Engineering, Technical University of Denmark3
Structured Electromagnetic Materials, Department of Photonics Engineering, Technical University of Denmark4
Center for Intelligent Drug Delivery and Sensing Using Microcontainers and Nanomechanics, Department of Health Technology, Technical University of Denmark5
Localized surface plasmon resonances (LSPR) and plasmon couplings in Ag capped Si Nanopillar (Ag NP) structures are studied using 3D FEM simulations and dark-field scattering microscopy. Simulations show that a standalone Ag NP supports two LSPR modes, i.e. the particle mode and the cavity mode. The LSPR peak position of the particle mode can be tuned by changing the size of the Ag cap, and can be hybridized by leaning of pillars.
The resonance position of the cavity resonance mode can be tuned primarily via the diameter of the Si pillar, and cannot be tuned via leaning of Ag NPs. The presence of a substrate dramatically changes the intensity of these two LSPR modes by introducing constructive and destructive interference patterns with incident and reflected fields.
Experimental scattering spectra can be interpreted using theoretical simulations. The Ag NP substrate displays a broad plasmonic resonance band due to the contribution from both the hybridized particle LSPR and the cavity LSPR modes.
Language: | English |
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Year: | 2015 |
Pages: | 12965-12978 |
ISSN: | 10944087 |
Types: | Journal article |
DOI: | 10.1364/OE.23.012965 |
ORCIDs: | Wu, Kaiyu , Rindzevicius, Tomas , Xiao, Sanshui and Boisen, Anja |