Plasmonic effects in composite metal nanostructures for sensing applications
We have investigated numerically the plasmonic effect on a two-dimensional periodic array of metallic nanostructures. The unit cell of the array has an Ag nanosphere and nanorod pair formed in a single structure. Three-dimensional finite element method is used for the study on the sensing performance within the optical spectra. The study takes into account the influences of the structural and material parameters, the rotational angle of the metal nanostructure, the number of metal nanostructure per unit cell, and the localized surface plasmon resonances. The proposed nanostructures function as a refractive index sensor with a sensitivity of 400 nm/RIU (RIU is the refractive index unit), showing the characteristics of low transmittance (T = 3.90%), high absorptance (A = 94.5%), and near-zero reflectance (R = 0.15%), could be achieved by a triangular arrangement of nanostructures within a unit cell. We also show how the tailoring of the structural parameters relates to the specific sensing schematics of the sensor.
KeywordsComposite metal nanostructures Plasmonic sensor Metal nanoparticles Modeling and simulation
This work was supported by the University Research Grant of Universiti Brunei Darussalam (grant no. UBD/OAVCRI/CRGWG (004)/170101) and Ministry of Science and Technology of Taiwan (MOST 106-2112-M-019-005-MY3).
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
- Chou Chau YF, Chou Chao CT, Rao JY, Chiang HP, Lim CM, Lim RC, Voo NY (2016a) Tunable optical performances on a periodic array of plasmonic bowtie nanoantennas with hollow cavities. Nanoscale Res Lett 11: 411Google Scholar
- Gresho PM, Sani RL (2000) Incompressible flow and finite element method, vol 1, 2. Wiley, New YorkGoogle Scholar
- Hairer E, Lubich C, Wanner G (2006) Geometric Numerical Integration, Springer, BerlinGoogle Scholar
- Horprathum M, Eiamchai Kaewkhao P, Chananonnawathorn J, Patthanasettakul CV, Limwichean S, Nuntawong N, Chindaudom P (2014) Fabrication of nanostructure by physical vapor deposition with glancing angle deposition technique and its applications. AIP Conference Proceedings 1617:7CrossRefGoogle Scholar
- Hu CC, Yang W, Tsai YT, Chau YF (2014) Gap enhancement and transmittance spectra of a periodic bowtie nanoantenna array buried in a silica substrate. Opt Commun 2014(324):227–233Google Scholar
- Xu X, Yang Q, Wattanatorn N, Zhao C, Chiang N, Jonas SJ, Paul SW (2017) Multiple-patterning nanosphere lithography for fabricating periodic three-dimensional hierarchical nanostructures. ACS Nano11: 10384–10391Google Scholar