Refractive index change from electron/hole concentration in waveguide

Hi


I am trying to simulate a wave guide electro-optic device/ switch and I need to perform the following steps.


1) Create an electrical model to solve for the concentrations of electrons and holes in a wave guide at a given voltage lets say Vx.

2) Convert these electrons and hole concentrations into a change in refractive index using some simple linear equations, I assume by simply going through each grid point.

3) Solve the mode for the wave guide as a result of the modified refractive index created by the electrons and holes at voltage Vx and calculate the phase change caused by the the electron hole distribution overlapping with the mode in the waveguide.

I have not used Comsol before and I'm a complete beginner. Would anyone be able to direct me to some resources e.g possible models and examples, tutorials which would help with processes 1, 2, and 3.

Thanks