This code reproduces the figures from

"Plasmonic sensors beyond the phase matching condition: a simplified approach"

By Alessandro Tuniz, Alex Y. Song, Giuseppe Della Valle, and C. Martijn de Sterke

Sensors 22(24), 9994 (2022) https://doi.org/10.3390/s22249994

For research purposes only.

Please cite the above paper if using any portion of this code for your research.

Creative Commons License (LICENSE-CC-BY-NC-SA).

Written by Alessandro Tuniz

main.ipynb can be run in its entirety to reproduce all figures in the paper

examples/load_modes_plot_transmission.ipynb allows you to load relevant effective index tables and obtain the transmission through a device of length L

Paper Abstract:

The conventional approach to optimising plasmonic sensors is typically based entirely on ensuring phase matching between the excitation wave and the surface plasmon between two semi-infinite media. However, this leads to suboptimal performance, even in the conventional Otto geometry. We present a simplified coupled mode theory approach for evaluating and optimizing the sensing properties of plasmonic waveguide refractive index sensors. It only requires the calculation of propagation constants, without the need for calculating overlap integrals.
We apply out method by evaluating the wavelength-, device length- and refractive index-dependent transmission spectra for an example silicon-on-insulator-based sensor of finite length. This reveals all salient spectral features which are consistent with full-field finite element calculations. This work provides a rapid and convenient framework for designing dielectric-plasmonic sensor prototypes.