Does the "simulation temperature" setting in MODE do anything?


I tried to change the “simulation temperature” in the general tab of FDE or varFDTD (default value is 300K). I was expecting Neff of a silicon WG to change due to silicon’s thermo-opto effect. However, the simulation results do not appear to change al all with different temperature values. Is this how it should be?


Help required to calculate the effective index of sub-wavelength gratings
Transmission from a thin plasmonic layer - FDTD vs Theory

Dear @chuan.xie

The value for simulation temperature will be important if you use a perturbed index material. To add such a material, click on Add and then select index perturbation in Material Database:

In the simulation file attached, I have two silicon rectangles. These two rectangles have different materials, and index for rectangle 1 is a function of temperature. By setting different values for simulation temperature you can study how the index varies:

As you can see in the figure above, only rectangle 1 (the top rectangle) is affected by simulation temperature.

I hope this answered your question.

index_perturbed_test.lms (279.2 KB)


This simulation failed. Please contact Lumerical Technical Support
Transmission from a thin plasmonic layer - FDTD vs Theory

Dear Behzad,
This is a perfect answer to my question. Thank you so much.