Refractive index of Kapton

import lightsmith as ls

# Kapton: Kumar et al. 2011: n 0.41–0.65 µm, k 0.49–0.78 µm
kapton = ls.fetch_refractiveindex("other", "Kapton", "Kumar", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(kapton.range_nm)  # (410, 650) nm
eps = kapton.eps([633])  # complex permittivity

import json, urllib.request
import lightsmith as ls

url = "https://materials.lightsmith.dev/v1/datasets/ds_6f909b4e5723/lightsmith"
kapton = ls.Tabulated.model_validate(json.load(urllib.request.urlopen(url)))
print(kapton.source)  # citation and provenance travel with the data

# ... load kapton as above, then:
sim = ls.Simulation(
    particles=[ls.Particle(shape=ls.Sphere(radius_nm=50), material=kapton)],
    medium_index=1.0,
    wavelengths=ls.WavelengthRange(start_nm=410, stop_nm=650, num=81),
)
res = ls.solve(sim)  # exact Mie for a sphere
print(res.q_ext)     # extinction efficiency at each wavelength