Mie Scattering from a 3D Dielectric Sphere

Understanding how light interacts with particles is essential across many fields, from optical engineering and advanced materials to biomedical applications and atmospheric science. When particles are comparable in size to the wavelength of light, Mie scattering provides a critical framework for accurately describing electromagnetic wave interactions.

Mie scattering is derived from the full solution of Maxwell’s equations and describes how an electromagnetic plane wave scatters from a homogeneous spherical particle. Unlike Rayleigh scattering, which applies to particles much smaller than the wavelength, or optical scattering approximations for much larger particles, Mie scattering requires a complete analytical solution based on an infinite series of spherical multipole partial waves.

Because no simple approximation exists for Mie scattering, accurate computational modelling is essential for analyzing these complex interactions. This application note explores how FullWAVE FDTD, RSoft’s finite-difference time-domain Maxwell equation solver, can be used to directly simulate the Mie scattering problem with results that closely match established Mie theory.

The example demonstrates simulation of electromagnetic scattering from a three-dimensional dielectric sphere, highlighting the accuracy and flexibility of the FullWAVE FDTD approach. By solving Maxwell’s equations directly, engineers can gain detailed insight into scattering behavior without relying solely on analytical methods.

The capabilities demonstrated in this application note can be extended beyond simple spherical particles to more complex structures and real-world applications. FullWAVE FDTD provides a versatile platform for investigating light–matter interactions in areas including atmospheric modelling, cancer detection and treatment, parasitology, metamaterials, and biophotonics.

By enabling precise simulation of Mie scattering effects, FullWAVE FDTD helps researchers and engineers evaluate optical phenomena, optimize designs, and accelerate innovation in emerging photonics applications.