Case Study: CNRS achieves rapid, accurate characterization of optical nanoresonators with COMSOL Multiphysics

Nanoresonators Get New Tools for their Characterization

CNRS researchers at Laboratoire Ondes et Matière d’Aquitaine faced the challenge of accurately characterizing optical nanoresonators — metal nanostructures with complex shapes whose electromagnetic behavior at subwavelength scales is difficult to model and traditionally requires heavy, excitation‑by‑excitation brute‑force simulations. To address this, the team used Comsol’s simulation platform, implementing COMSOL Multiphysics with the RF Module and interfacing it with MATLAB to build a reliable numerical framework.

Using Comsol, the team developed an analytical‑numerical modal method that computes and normalizes quasinormal modes and their excitation coefficients (via volume integrals), allowing rapid prediction of scattered fields, scattering/absorption cross sections, radiation diagrams, and decay rates without repeating full simulations for each excitation. The Comsol‑based results matched full vectorial computations while greatly reducing computational effort, speeding characterization and enabling broader application of nanoresonators in areas such as photovoltaics, spectroscopy, sensors and NEMS.

CNRS

Mathias Perrin

Scientist