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Ansys Learning Forum Forums Discuss Simulation Photonics Issue in HEAT simulation of FEEM Heat Solver Reply To: Issue in HEAT simulation of FEEM Heat Solver

Guilin Sun
Ansys Employee

Sorry to reply you late.

crystallization temperature is for bulk material, I believe. When it is nano scale, the thermal properties are different from bulk. I read a paper saying that the value can change to be 2/3. Thus using the bulk properties to predict the nano-scale structure is not accuate.

I would suggest you to check:
if the HEAT settings are proper, including material properties;

You mentioned FDE. that means you are simulating a waveguide and find the neff change due to temperature.  make sure the optical material property is proper.

If you know the dn/dT, probaly you can manually calculate the refractive index change without using the waveguide mode. This thermal coefficient also changes with thickness. 

As long as the simulation settings are correct, the result is reliable, provided that in experiment the meterial properties are the same as what you simulate. The HEAT solver is linear so it is unlikely the result is wrong when the settings are correct. eg, the boundary conditions are correct. Please note that the HEAT solver region is quite small in general so make sure the temperature is correct.