# Encoding: utf-8
"""Sellmeier dispersion."""
import numpy.typing as npt
from .base_dispersion import Dispersion
[docs]
class SellmeierCustomExponent(Dispersion):
r"""Sellmeier dispersion with custom exponents.
Single parameters:
--
Repeated parameters:
:A: Coefficient for n\ :sup:`2` contribution. Defaults to 0.
:e_A: Exponent for the wavelength in the numerator. Defaults to 1.
:B: Resonance wavelength. Defaults to 0. Unit in µm\ :sup:`-2`.
:e_B: Exponent for B. Defaults to 1.
Output:
.. math::
\varepsilon(\lambda) = \sum_j \boldsymbol{A}_j
\cdot \lambda^{\boldsymbol{e_A}j} /(\lambda^2 - \boldsymbol{B}_j^{\boldsymbol{e_B}j})
With :math:`j` as the index of the respective oscillator.
"""
single_params_template = {}
rep_params_template = {"A": 0, "e_A": 1, "B": 0, "e_B": 1}
def dielectric_function(self, lbda: npt.ArrayLike) -> npt.NDArray:
lbda = lbda / 1e3
return sum(
c.get("A") * lbda ** c.get("e_A") / (lbda**2 - c.get("B") ** c.get("e_B"))
for c in self.rep_params
)