Cylinder: Qabs vs Diameter

This example demonstrates how to compute and visualize the scattering efficiency (Qsca) as a function of diameter for cylindrical scatterers using PyMieSim.

Importing the package dependencies: numpy, PyMieSim

import numpy as np
from TypedUnit import ureg

from PyMieSim.experiment.scatterer import Cylinder
from PyMieSim.experiment.source import Gaussian
from PyMieSim.experiment import Setup
from PyOptik import Material

Defining the source

source = Gaussian(
    wavelength=400 * ureg.nanometer,  # 400 nm
    polarization=0 * ureg.degree,  # Linear polarization angle in radians
    optical_power=1e-3 * ureg.watt,  # 1 milliureg.watt
    NA=0.2 * ureg.AU,  # Numerical Aperture
)

Defining the scatterer distribution

scatterer = Cylinder(
    diameter=np.linspace(1, 800, 300)
    * ureg.nanometer,  # Diameters ranging from 1 nm to 800 nm
    property=[
        Material.silver,
        Material.gold,
        Material.aluminium,
    ],  # Scatterer materials
    medium_property=1 * ureg.RIU,  # Refractive index of the surrounding medium
    source=source,
)

Setting up the experiment

experiment = Setup(scatterer=scatterer, source=source)

Measuring the scattering efficiency (Qsca) Note: The original request mentioned Qsca, but the measurement code uses Qabs. If Qsca measurement is intended, ensure to use the correct measure object from PyMieSim.

dataframe = experiment.get(
    "Qabs"
)  # Assuming Qabs was intended, replace with measure.Qsca if needed

Plotting the results Visualizing how the scattering efficiency varies with the cylinder diameter.

dataframe.plot(x="scatterer:diameter")

<Figure size 800x500 with 1 Axes>