Paper
2 March 2020 Simulation of a parallel waveguide array structure suitable for interrogation scheme in a plasmonic biosensor
João Costa, Alessandro Fantoni, Paulo Lourenço, Manuela Vieira
Author Affiliations +
Abstract
Surface plasmon resonance sensors have emerged has one of the most suitable approaches for biosensing. A common approach consists of exciting the plasmons at the interface between a functionalized metal film and a sample medium containing the analyte. The propagation of the surface plasmon is highly dependent on changes of the refractive index of the surrounding environment thus providing a mechanism for sensing. The typical interrogation schemes are based on scanning over the wavelength or the incident angle to search for the resonance condition. These solutions require additional motor-driven rotation stages, prisms or other bulky components, introducing complexity which prevents the fabrication of fully on-chip devices. This work reports a simulation study of an amorphous silicon waveguide structure consisting of an array of parallel surface plasmon interferometers with different propagation lengths, each one comprising a thin layer of gold embedded into a-Si:H waveguide. The surface plasmon modes at the end of the plasmonic structure can interfere constructively or destructively depending on the refractive index of the analyte and the interferometer’s length. The variation of the output intensity at the end of each element of the array provides a convenient interrogation scheme that is suitable for on-chip integration. In this paper we investigate this setup and analyze the output power at the end of the array as a function of the refractive index of the sampling medium. The setup is simulated and characterized by the eigenmode expansion method.
© (2020) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
João Costa, Alessandro Fantoni, Paulo Lourenço, and Manuela Vieira "Simulation of a parallel waveguide array structure suitable for interrogation scheme in a plasmonic biosensor", Proc. SPIE 11274, Physics and Simulation of Optoelectronic Devices XXVIII, 112742B (2 March 2020); https://doi.org/10.1117/12.2546178
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Waveguides

Interferometers

Refractive index

Wave propagation

Plasmons

Sensors

Interfaces

RELATED CONTENT


Back to Top