Paper
25 April 2012 Plasmonic device using backscattering of light for enhanced gas and vapour sensing
Michaël Lobet, Olivier Deparis
Author Affiliations +
Abstract
Based on recent experimental and theoretical results obtained with gold-glass nanocomposite films, we propose a plasmonic device which uses the backscattering of light in order to make a highly sensitive gas/vapour sensor. The backscattered reflectance is used as the sensing signal since it has been shown, under certain conditions, that this component of the diffracted light is much more sensitive to a change of refractive index in the surrounding medium than the specular component. In addition, the backscattering presents an azimuthal angular dependency which is viewed as an advantage for practical implementation. The device consists of three planar layers. First, a glass substrate acting as incidence medium. Then a dielectric layer with a reduced refractive index with respect to the substrate is added which acts as a leaky-waveguide in order to maximize light coupling into the third sensing layer. The third layer is composed of gold nanopillars embedded in a dielectric matrix. Through numerical simulations, 2D periodic square and hexagonal arrays of gold nanopillars are compared in order to point out the influence of the nanocomposite arrangement in the photonic response. Moreover, disorder is introduced into these arrays in order to highlight the robustness of the sensing principle with respect to defects in the particle arrangement and size. For the purpose of gas/vapour sensing, we study the backscattered reflectance as it changes according to modifications in the dielectric environment at the external surface due to adsorption from gas or vapour. We determine the optimized device parameters and incidence angles.
© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Michaël Lobet and Olivier Deparis "Plasmonic device using backscattering of light for enhanced gas and vapour sensing", Proc. SPIE 8425, Photonic Crystal Materials and Devices X, 842509 (25 April 2012); https://doi.org/10.1117/12.921870
Lens.org Logo
CITATIONS
Cited by 2 scholarly publications.
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Backscatter

Plasmonics

Dielectrics

Gold

Nanocomposites

Reflectivity

Refractive index

Back to Top