Reply To: The way to plot imaginary part of refractive index (k) as a function of Power

[Guilin Sun]

Do you mean the material index with perturbation, or the effective index of the mode?

The conversion theory is here  https://optics.ansys.com/hc/en-us/articles/360034382494-Charge-distribution-to-change-in-refractive-index-theory

So if the charges are uniform, you can get the perturbated material complex refractive index:

If the np density is simulated from CHARGE, it is not uniform then you cannot import or get the refractive index perturbation.

However when the np density is applied to a waveguide, and you use FDE or FEEM you will be able to get the mode effective index, real and imaginary parts.