mcmahon-lab/2d-programmable-waveguide

How mcmahon-lab/2d-programmable-waveguide works

This repository is a compact demo toolkit for simulating programmable 2D photonic waveguides and exploring inverse design, classification, multimode transformations, and physics-aware training. The user-facing workflow is to run a Jupyter example, define or optimize an index pattern and input field, then simulate propagation and inspect the output. The library supplies the propagation solver, waveguide geometry, mode and beam utilities, and training helpers. Notebook-to-module links follow the README’s descriptions; source-level edges are limited to relationships shown in the excerpts or SOURCE INDEX.

Main entry points: split_step_solver.py BPM propagation · Example 1 Y-splitter.ipynb Y-splitter · Example 2 Inverse design.ipynb Inverse design · Example 3 MNIST classification.ipynb MNIST classification

Components 16

Demonstration notebooks

Y-splitter Example 1 Y-splitter.ipynb
Inverse design Example 2 Inverse design.ipynb
MNIST classification Example 3 MNIST classification.ipynb
Mode conversion Example 4 Mode conversion in multimode waveguide.ipynb
Multimode MVM Example 5 Matrix-vector-multiplication in multimode waveguide.ipynb
Mismatched passes Example 6 Mismatched forward-backward pass.ipynb

Waveguide physics

Waveguide geometry tdwg_lib/waveguide.py
BPM propagation tdwg_lib/split_step_solver.py
Eigenmode solver tdwg_lib/mode_solver.py
Beam and mode fields tdwg_lib/beam_utils.py

Numerical utilities

PyTorch Fourier tools tdwg_lib/ftutils_torch.py
NumPy Fourier tools tdwg_lib/ftutils_np.py
Smoothing helpers tdwg_lib/helpers.py

Design and training

PAT autograd tdwg_lib/pat.py
Training utilities tdwg_lib/pnn_utils.py

Other components

Researcher

Connections 15

Researcher → Y-splitter: runs example README.md
Researcher → Inverse design: runs example README.md
Researcher → MNIST classification: runs example README.md
Researcher → Mode conversion: runs example README.md
Researcher → Multimode MVM: runs example README.md
Researcher → Mismatched passes: runs example README.md
Y-splitter → BPM propagation: simulates propagation README.md
Inverse design → BPM propagation: optimizes simulation README.md
Mode conversion → BPM propagation: demonstrates propagation README.md
Multimode MVM → BPM propagation: designs transformation README.md
MNIST classification → BPM propagation: classifies with waveguide README.md
Mismatched passes → PAT autograd: uses PAT approach README.md
Waveguide geometry → PyTorch Fourier tools: builds frequency axis tdwg_lib/waveguide.py
BPM propagation → PyTorch Fourier tools: uses frequency axis tdwg_lib/split_step_solver.py
Eigenmode solver → NumPy Fourier tools: uses transforms tdwg_lib/mode_solver.py

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