Examples

A guided path from “load a layout” to “run it on any FDTD engine and read the S-parameters.” Each entry below is a real Jupyter notebook, executed and committed with its outputs, so the plots and numbers you see are the actual solver output.

Every notebook reproduces for free: the live runs use beamz (Apache-2.0 JAX FDTD, on CPU) or tidy3d’s free local mode solver, and the cross-engine comparisons load recorded tidy3d/Lumerical artifacts. No cloud account, license, or GPU is required to run any of them.

The source of truth for each notebook is a paired .py (jupytext percent format) under examples/; see examples/README.md for how to run them.

#	Notebook	You’ll learn
00	00 · Quickstart — a layout to S-parameters in ten lines	Layout → S-matrix in ten lines, on the free engine.
01	01 · From a GDS layout to a Component	Load a GDS / gdsfactory cell, auto-detect ports, read the geometry view.
02	02 · Technology & materials	Materials, the vertical layer stack, and (in 02b) refractiveindex.info sources across engines.
03	03 · Your first simulation	The full flow end-to-end: geometry → permittivity → build → run → S-params → fields.
04	04 · Reading results — everything an SMatrix tells you	SMatrix: insertion loss, crosstalk, phase, reciprocity/passivity, Touchstone/HDF5/npz I/O.
05	05 · Fields and modes	Waveguide mode profiles, effective indices, and permittivity cross-sections.
05b	05b · Field monitors: where they sit, what they record	Field monitors: axes, pinned positions, recorded wavelengths, and plot_monitor_planes — with the Si→SiN escalator’s side view.
06	06 · Convergence, caching, and cross-validation	Mesh-convergence sweeps, run_cached (repeat runs free), and cross-engine validation where converged ≠ correct.
07	07 · Choosing an engine — three solvers, one job	The identical job on beamz / tidy3d / Lumerical, and how they agree.
08	08 · Any EDA in, any engine out	Any EDA in, any engine out: gdsfactory / SiEPIC / raw-GDS frontends, then the full frontend × engine matrix.
09	09 · The CLI and serializable jobs	The gds-fdtd CLI and serializable JobSpec for remote/batch compute.
10	10 · Cookbook — the Si→SiN escalator on the free engine	Reference devices with known-good S-params — the Si→SiN escalator on the free engine.
10b	10b · Polarization: a splitter and a splitter-rotator	Polarization splitter and splitter-rotator from gdsfactory: TE/TM modes, multi-mode S-params, and per-polarization fields on two engines.
11	11 · A Bragg grating: the stopband, seen in the field	A 95 µm SiEPIC Bragg grating on tidy3d: the stopband spectrum, and the same field monitor in-band (reflected) vs out-of-band (transmitted).