Cylinder: Qsca vs Wavelength

This example demonstrates how to compute and visualize the scattering efficiency (Qsca) as a function of wavelength for cylindrical scatterers using PyMieSim, considering cylinders with different diameters and refractive indices.

Importing the package dependencies: numpy, PyMieSim

import numpy as np
from PyMieSim.experiment.scatterer import Cylinder
from PyMieSim.experiment.source import Gaussian
from PyMieSim.experiment import Setup
from PyMieSim.units import nanometer, degree, watt, AU, RIU

Defining the source Studying the scattering efficiency across a range of wavelengths.

source = Gaussian(
    wavelength=np.linspace(400, 1000, 150) * nanometer,  # Wavelengths ranging from 400 nm to 1000 nm
    polarization=0 * degree,  # Linear polarization angle in radians
    optical_power=1e-3 * watt,  # 1 milliwatt
    NA=0.2 * AU  # Numerical Aperture
)

Defining the scatterer distribution Considering cylinders with specific diameters and refractive indices.

scatterer = Cylinder(
    diameter=[200, 150] * nanometer,  # Array of diameters: 200 nm, 150 nm, 100 nm
    property=[2, 3, 4] * RIU,  # Array of refractive indices: 2, 3, 4
    medium_property=[1] * RIU,  # Refractive index of the surrounding medium
    source=source
)

Setting up the experiment

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

Measuring the scattering efficiency (Qsca) Averaging the data across the different indices to simplify visualization.

dataframe = experiment.get('Qsca')

Plotting the results Visualizing how the Qsca varies with wavelength for the given cylinder configurations.

dataframe.plot_data(x='source:wavelength', std='scatterer:property')