MiePy is a Python module for the generalized multiparticle Mie theory (GMMT), also known as the aggregate T-matrix method. MiePy solves the electrodynamics of a collection of spherical or non-spherical scatterers with an arbitrary incident source.

Electric field around a 37 particle cluster

3D electric field contours around three metal nanoparticles

• Non-spherical particles using the T-matrix formulation via the null-field method with discrete sources (NFM-DS). Includes cylinders, spheroids, ellipsoids, cubes and polygonal prisms
• Arbitrary incident sources (plane waves, Gaussian beams, HG and LG beams, point dipoles)
• Evaluation of cluster cross-sections and optical force and torque on individual particles
• Periodic boundary conditions with various lattice types (square, hexagonal, etc.) and mirror and discrete rotational symmetries for faster calculations
• Optional planar interface (substrate)
• 3D scene visualization using the VPython library
• Image clusters using a simulated microscope
• OpenMP parallelization for systems with larger numbers of particles

pip install miepy

If using uv:

uv venv --python 3.13
uv pip install miepy
source .venv/bin/activate

For examples and use cases, see examples folder.

For an overview of the theory, see docs folder.

MiePy uses vcpkg for C++ dependency management and uv for Python management, which simplifies building across platforms.

Prerequisites:

• GCC and GFORTRAN
• uv

Build steps:

1. Clone MiePy and its submodules:

git clone https://github.com/johnaparker/miepy.git miepy --recurse-submodules && cd miepy

2. Bootstrap vcpkg (first time only):

./vcpkg/bootstrap-vcpkg.sh

3. Install MiePy using uv:

uv sync

4. Optionally, run the tests to verify correctness:

uv run pytest tests

MiePy is licensed under the terms of the GPLv3 license.