BeamZ v0.6.0

Added

• Added end-to-end differentiable FDTD with portable JAX and accelerated native
  CUDA reverse-mode execution, checkpointing, and differentiable modal objectives.
• Added 2D and volumetric 3D topology inverse design with autodiff and spectral
  adjoint gradients, broadband objectives, schedules, and fabrication-aware exports.
• Added dispersive materials, a bundled optical material library, Bloch-periodic
  boundaries, and executed metasurface and CMOS RGB sensor examples.
• Added consistent full-tensor dielectric ports on uniform and rectilinear grids,
  native CUDA full-tensor updates, and compact JAX/CUDA material storage.
• Added experimental CUDA multistep scheduling and opt-in region rasterization
  for Gmsh-derived scenes.
• Added passive SOI differential benchmarks and expanded inverse-design,
  grating-coupler, and interface-smoothing notebooks and validation reports.

Changed

• BeamZ now requires Python 3.11–3.14. Python 3.10 users must upgrade their
  environment before installing v0.6.0.
• The optional CUDA component is now version 0.30.0 / ABI 30. Rebuild the
  extension when upgrading from an earlier ABI.
• Reduced CPML and material storage overhead, reused modal solves, and improved
  sharded CUDA storage selection and arithmetic consistency.
• Updated dependencies for security fixes and added locked Python and Rust
  dependency audits in CI.

Fixed

• Corrected 2D mode launch and extraction in all four directions, normal Yee
  sampling in 3D modal projection, tensor-axis mapping, and symmetric mode seeds.

• Made forced mode mirror symmetry opt-in and stabilized CPML coefficients,
  including timestep-independent default alpha and compact 2D profiles.

• Fixed electrical conductivity binding in differentiable simulations.

• Fixed topology contours shrinking away from design-region boundaries (#331).
  Region clearing now uses exact cell footprints and fixed geometry supplies
  interpolation context in TopologyProblem.

• Added mode="pixel_exact" and optional bilinear contour sample_spacing to both
  optimization export workflows, and fixed solid/void masks for port cells.

• Added explicit GDS coordinate precision and material/layer selection, preserving
  holes without intermediate quantization through a global layout grid.

• Added a runnable mode-converter export showcase with GDS round-trip geometry and
  transmission comparisons on 100 nm and 50 nm meshes.

Execution limits

• Native CUDA full-tensor updates require canonical, unpadded float32 streamed
  storage. Full-tensor gradients use JAX; CUDA multistep scheduling has a narrower
  supported physics and storage envelope. See CUDA documentation
  for backend requirements and measured performance limits.

What's Changed

• docs: update citation for BeamZ v0.5.3 by @QuentinWach in #312
• build(deps): bump pyo3 from 0.29.2 to 0.29.3 in the rust-minor-patch group by @dependabot[bot] in #313
• build(deps): bump the python-minor-patch group with 2 updates by @dependabot[bot] in #314
• fix: make default CPML alpha independent of timestep by @QuentinWach in #317
• Revert #317 before replacing it with a minimal CPML fix by @QuentinWach in #318
• fix: keep CPML alpha fixed under timestep refinement by @QuentinWach in #319
• test: verify compiled CPML alpha defaults in 2D and 3D by @QuentinWach in #321
• test: add passive SOI benchmarks with stable DFT clocks by @teevee112 in #245
• feat: add broadband dispersive media, periodic boundaries for CMOS RGB sensor example by @QuentinWach in #233
• feat: add Bloch meta-atom optics and executed metasurface notebooks by @QuentinWach in #323
• build(deps): bump fsspec from 2026.1.0 to 2026.6.0 by @dependabot[bot] in #324
• docs: restore README to October 7, 2026 version by @QuentinWach in #325
• fix: make sharded CUDA storage selectable with consistent arithmetic by @vvahidd in #329
• feat: add topology inverse design with adjoint and autodiff workflows by @QuentinWach in #327
• [Docs]: Revise example links in README.md by @QuentinWach in #332
• [Docs]: Update inverse design description in README by @QuentinWach in #333
• Fix topology GDS boundary gaps and add explicit export modes by @QuentinWach in #335
• build(deps): bump hypothesis from 6.168.3 to 6.168.5 in the python-minor-patch group by @dependabot[bot] in #339
• Add volumetric inverse design and grating coupler notebook by @QuentinWach in #336
• test: fix float32 objective sign tolerance in main CI by @QuentinWach in #340
• perf(boundaries): store uniform 3D CPML constants as scalars; add interface smoothing report by @cdaunt in #341
• Add accelerated CUDA reverse-mode FDTD with portable JAX imports by @QuentinWach in #338
• Add experimental CUDA multistep scheduling based on PR #308 by @QuentinWach in #334
• Add experimental Futhark execution backend by @pepijndevos in #308
• Reduce modal projection overhead by reusing mode solves by @QuentinWach in #344
• Stabilize CPML coefficients and compact 2D profiles by @QuentinWach in #345
• Fix electrical conductivity binding in differentiable simulations by @QuentinWach in #349
• Fix 2D mode launch and extraction in all four directions by @QuentinWach in #350
• build(deps): bump the rust-minor-patch group with 2 updates by @dependabot[bot] in #351
• build(deps): bump the python-minor-patch group with 2 updates by @dependabot[bot] in #352
• fix(modes): make forced mirror symmetry opt-in by @QuentinWach in #357
• fix(analysis): account for normal Yee sampling in 3D modal projection by @QuentinWach in #358
• Add consistent full-tensor ports and compact JAX/CUDA material updates by @QuentinWach in #362
• Fix material tensor axis mapping in mode solves by @QuentinWach in #367
• Fix missing symmetric permittivity entries in mode seeds by @QuentinWach in #368
• build(deps): bump gitpython from 3.1.62 to 3.2.1 by @dependabot[bot] in #372
• build(deps): bump black from 26.3.1 to 26.10.1 by @dependabot[bot] in #373
• docs: make AI contribution disclosure optional by @QuentinWach in #378
• fix(deps): update certifi and Pillow security fixes by @QuentinWach in #379
• fix!: require Python 3.11 and patched Pillow by @QuentinWach in #380
• ci: audit locked Python and Rust dependencies by @QuentinWach in #381
• Add opt-in region rasterization for Gmsh-derived scenes by @vvahidd in #370
• chore(release): prepare BeamZ v0.6.0 by @QuentinWach in #383
• fix(docs): unblock v0.6.0 release qualification by @QuentinWach in #385

New Contributors

• @cdaunt made their first contribution in #341
• @pepijndevos made their first contribution in #308

Full Changelog: v0.5.3...v0.6.0