Your source of photonics CAD tools


A powerful waveguide mode solver

Mode Solvers

FIMMWAVE supports a number of different and complementary mode solvers, each adapted and optimised to solve certain types of waveguide geometries. All the mode solvers are compatible with FIMMPROP, our innovative EigenMode-Expansion propagation tool.

The solvers implemented in FIMMWAVE are:

FMM Solver
The FMM Solver

This solver, based on the Film Mode Matching method, is optimised for rectangular waveguide structures.
FDM Solver
The FDM Solver

Based on an advanced finite-difference algorithm; this solver is ideal for metallic or absorbing structures. It can accurately model waveguides with high-step refractive index profiles, slanting/curved interfaces and gradient profiles.
FDM Solver
The FEM Solver

A mode solver based on the finite-element method, ideal for complex geometries, especially with curved interfaces, e.g. photonic crystal fibres. Offered as an optional add-on to the FIMMWAVE base module.
Effective Index Solver
The Effective Index Solver

Based on the Effective Index Approximation, this is a very fast solver for quasi-2D structures.
FDM Solver
Fibre Solvers

FIMMWAVE offers a variety of Fibre Solvers to solve any kind of profile with a circular symmetry. Some of them are offered as an optional add-on to the FIMMWAVE base module.

Complex versions are available for most solvers, allowing losses and even metals to be modelled.

Bend modes can be calculated using the FMM, FDM and FEM Solvers with the Complex Engine.

Full Mode Solver Feature Table (PDF version here)