Diamond WG Comsol 3D Sim
The project concerns the computation of the electric field propagation inside a diamond waveguide using finite domain time difference (FDTD) and a time dependent approach. 3D simulations of a reduced scale model will performed. Several geometries will be studied: - a perfectly smooth waveguide without analyte, - a perfectly smooth waveguide with analyte on top, - an imperfect waveguide with a rugged profile without analyte, - an imperfect waveguide with a rugged profile with analyte on top. For each pair of models, the analyte absorption spectrum will be computed for infrared wavelength (5.6-11.2 µm) as the ratio of the transmitted intensity with analyte on the intensity without analyte. The goal is to determine the roughness influence on the absorption spectrum. Then, we will be able to compare our experimental results to the numerical one. This will improve the scope of our previous paper which assumed losses due to roughness based on purely theoretical considerations. Once the results are similar, the geometry of our waveguide roughness can be assumed and the comparison results can be published into a peer-reviewed paper. Finally, the project will progress to the next steps which are the analysis of proteins related to mental diseases and the determination of the optical setup sensitivity limits. During the simulations, several roughness geometries will be tested to mimic the experimental reality and two well know analytes (isopropanol and acetone) will be introduced as spectra in the simulation to be computed in the infrared domain. The advantages of using a cluster compared to our available computers are a higher number of cores with a larger available RAM enabling the 3D simulations required for roughness analysis.