complex indices for materials in write_sparameters_lumerical

[jan-david-fischbach]

Is your feature request related to a problem? Please describe.
Cannot use (n,k) Materials in Lumerical in the current state

Describe the solution you'd like
Enable passing a complex index to write_sparameters_lumerical (thru material_name_to_lumerical). This could be done by adding the following snippet to handle the complex index:

elif isinstance(material, complex):
            mat = s.addmaterial("(n,k) Material")
            s.setmaterial(mat, "Refractive Index", material.real)
            s.setmaterial(mat, "Imaginary Refractive Index", material.imag)
            s.setnamed(layername, "material", mat)

Note that setting the material in lumerical depending whether a str, int or float is used is repeated twice, once for the cladding and once for the layers. It might make sense to refactor that into a function.

[joamatab]

Hi @Jan-David-Black ,

yes, that's a great idea, thank you for sharing,

How does this new branch work for you?
https://github.com/gdsfactory/gdsfactory/tree/559

I made a new function set_material() as you suggested

[jan-david-fischbach]

Looks Great! I am sorry I only throw stuff in here and don't just open a pull request, with everything set up properly. At some point I will find the time configure a "build environment" so that I can contribute more efficiently!

[joamatab]

Im also trying it on my side

just pushed a fix, more docs and a demo

[jan-david-fischbach]

What was the problem with using complex instead of a tuple of floats?

[joamatab]

now it can do both tuples and complex refractive index

[jan-david-fischbach]

now it can do both tuples and complex refractive index

ah understood :)