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Surface plasmon resonance (SPR) of nanostructured thin metal films (so-called nanoplasmonics) has attracted intense attention due to its versatility for optical sensing and chip-based device integration. Understanding the underlying physics and developing applications of nanoplasmonic devices with desirable optical properties, e.g. intensity of light scattering and high refractive index (RI) sensitivity at the perforated metal film, is crucial for practical uses in physics, biomedical detection, and environmental monitoring. This work presents a semi-analytical model that enables decomposition and quantitative analysis of surface plasmon generation at a new complex nanoledge aperture structure under plane-wave illumination, thus providing insight on how to optimize plasmonic devices for optimal plasmonic generation efficiencies and RI sensitivity. A factor analysis of parameters (geometric, dielectric-RI, and incident wavelength) relevant to surface plasmon generation is quantitatively investigated to predict the surface plasmon polariton (SPP) generation efficiency. In concert with the analytical treatment, a finite-difference time-domain (FDTD) simulation is used to model the optical transmission spectra and RI sensitivity as a function of the nanoledge device's geometric parameters, and it shows good agreement with the analytical model. Further validation of the analytical approach is provided by fabricating subwavelength nanoledge devices and testing their optical transmission and RI sensitivity.
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Modeling surface acoustic wave coupled surface plasmon resonance in layered structures
Surface plasmon resonance is widely studied and used for chemical and biological sensing. Current technology is based on angle resolved resonance detection at specific optical wavelengths. That is, changes in the reflectivity at the resonant angles are correlated to the chemical or biological substance at the surface of the sensor. In this work, we discuss the modeling and numerical techniques used to analyze a method to characterize plasmon resonances through surface acoustic wave (SAW) coupling of the incident light. The design strategies used to optimize the sensing performance of layered structures is described for several materials that are typically used as substrates and thin films.
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- Award ID(s):
- 1827847
- PAR ID:
- 10550295
- Editor(s):
- Kim, Jaehwan
- Publisher / Repository:
- SPIE
- Date Published:
- ISBN:
- 9781510625938
- Page Range / eLocation ID:
- 11
- Format(s):
- Medium: X
- Location:
- Denver, United States
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1117/12.2514828
