Learning Forum

[abdulalim]

Hello there,

i am working on simulating the real and imaginary part of the dilectric complex function using Drude model , and i need to see how does the real and imaginary part of the equation change with increasing the temperature , so what i would like to ask about is how can i define the temperature using lumerical script language ,how would lumerical deal with that?

thank you in advanced

[Guilin Sun]

So you want to quantify the change of permittivity or refractive index with temperature, by use of Drude model?
If you have the relationship between wc and wp with temperature, sure you can do this, analytically.
In the case that the temperature is not high, the change of refractive index is linear in general. You just need to find the temperature coefficient to get the change of refractive index, and fit the Drude model. Since the change is a single value, but the permittivity Drude model has 3 or 2 variables: permittivity at infinite frequency in the first term, wc and wp, it can be difficult to get physical values, except that you have only one of them to change. For example, wc.
Otherwise, you will need to simulate the temperature using HEAT, and import the temperature attribute to FDTD or FDE. You will also need to specify the temperature coefficient.
Examples are
Thermally tuned waveguide (FDE)
Thermal switch