Refractive index of 4 level 2 electron gain medium

refractiveindex
fdtd
nonlinear
plugin
laser

#1

I am running simulations with laser gain medium modeled using 4-level 2-electron material system. I have selected a base material of refractive index 1.5 (dispersionless) for that gain medium.

However, I have noticed from the results of non-linear simulations using this material that real part of refractive index of the gain medium shows dispersion around the resonant frequencies. Is there any way to plot the variation of real part of the gain medium as a function of frequency ? Such plots are not accessible for gain mediums through material explorer in Lumerical.


#2

Hi,

Sorry I am not sure if I understand your question properly. It should be possible to use a dielectric material as the base material of the 4L2e material model. In that case, there should not be dispersion for the material, so I am a little confused, in particular:

Are you able to attach some screenshots to clarify things a little bit. Thanks!


#3

If using the a dielectric material as the base material of the four-level two-electron model as you said, how could I determine the parameters listed in the model, such as wa, wb, t30 and so on?


#4

These parameters will depend on the physics of the actual material. You can set the numbers without having to set a base material. The base material will just add the real and imaginary part of the index to the simulation. It should be better to use a base material but it is not a must.