Changelog

2.1.0 - 2026-11-06

Added

• parametric.extend_ports extends a component’s waveguide ports with straight sections, or with transitions to a new port specification, keeping the original port names.
• eo_s21 computes the electro-optic response of a terminated traveling-wave modulator in the frequency domain, from the same code and arguments as TerminatedModTimeStepper.
• lvs_check runs Siemens Calibre LVS with engine="calibre", and load_lvs_results reads its results, as DRC already could.
• Port names in Touchstone files: SMatrix.write_snp writes each port’s name and mode in an [Optical Port List] block, and SMatrix.load_snp reads them back when ports is not given. Argument comments replaces the block, and argument conjugate, also in load_snp, conjugates the data.
• Reference queries in the updates of CircuitModel.start can be path strings, such as "SUB/BEND[1]" or "**/COMP*": names separated by /, with * and ? wildcards, [i] for the i-th reference and ** for any depth. select_references lists the references a query selects.
• TimeStepper.write_verilog_a exports TerminatedModTimeStepper with frequency-dependent RF index, impedances or loss, given as an Interpolator or mode-solved, which it used to refuse: the exported module applies the time stepper’s own electro-optic response.
• AvalanchePhotodiodeTimeStepper, ElectroAbsorptionModTimeStepper and SemiconductorAmplifierTimeStepper export to Verilog-A with TimeStepper.write_verilog_a.
• Reference arrays in PDA projects: a Reference with several columns or rows is stored as one array, and the ports, terminals and connections of each element carry over.

Changed

• abstract.fiber is one component stepped in sections, instead of a chain of single-section components, and its default max_phase is 0.15: nonlinear spans run 2 to 5 times faster and are more accurate.
• The default max_phase of AnalyticWaveguideTimeStepper and AnalyticWaveguideModel.nonlinear is 0.15, up from 0.05: nonlinear waveguides need about three times fewer sections for a smaller error.
• The black_box_component of each model draws the model’s schematic symbol in a box with the model type below it, as the abstract components do, instead of a placeholder marked “BB”.
• A reference query in updates that selects no reference emits a RuntimeWarning, and an invalid query raises ValueError or TypeError instead of KeyError, RuntimeError or re.error.
• Gradient evaluation with Tidy3DModel reuses structure reconstructions and permittivity samples within an evaluation, reducing repeated work for parametric components.

Fixed

• AnalyticWaveguideTimeStepper takes its nonlinearity at the power halfway along each section rather than at its entrance, which removes a first-order error in lossy waveguides. It splits a nonlinear waveguide’s dispersion around its nonlinear steps, so the phase of generated light, such as a four-wave-mixing idler, converges as the square of the number of sections instead of linearly.
• TimeStepper.write_verilog_a now exports the self-heating of DMLaserTimeStepper: thermal rollover, the threshold shift and the thermal frequency drift.
• PhotodiodeTimeStepper pink noise follows 1/f at every time step and corner frequency.
• TimeStepper.write_verilog_a keeps the noise of a filtered PhotodiodeTimeStepper.
• TimeStepper.write_verilog_a now exports the nonlinear terms of RingTimeStepper.
• AnalyticWaveguideTimeStepper applies n_eff at reference_frequency, as AnalyticWaveguideModel does, rather than at the carrier.
• Dispersion in AnalyticWaveguideTimeStepper no longer lengthens a waveguide shorter than the default filter’s latency, such as a ring.
• The electro-optic response of TerminatedModTimeStepper near velocity matching.
• Ports of abstract components and black boxes lie on the grid.
• Improved load speed and robustness of pda.load_project on a project with a large DataModel.
• A string key in updates, such as "ARM", was read as one regular expression per character and silently selected nothing; strings are now path queries.
• copy.copy and copy.deepcopy of a Model, TimeStepper or RandomVariable keep its properties.

2.0.0 - 2026-10-14

Added

• reference_chain creates a chain of connected references from a text sequence, with explicit ports, mirroring, repetition and spacers.
• parametric.fill tiles a region with a structure or component at a fixed pitch, around keep-out layers.
• intersects tests whether two sets of structures overlap or touch.
• Argument min_width in parametric.transition, so that layers present on only one side of the transition do not taper down to zero width.
• Argument verbose in live_viewer.LiveViewer to silence its messages.
• live_viewer.LiveViewer works behind path proxies, such as code-server’s /proxy/<port>/, and accepts edits from the code-server host without extra settings.
• Terminals can be wired into nets in the LiveViewer’s layout view, as ports are, and the Properties panel lists a cell’s models with the active one marked.

Changed

• Breaking: target_neff in PortSpec and FiberPort defaults to None, which estimates it from the cross-section media at the solve frequencies. The port specifications in basic_technology use this new setting.
• Ports whose specifications differ only in target_neff can be connected directly, including designs saved with the previous basic_technology.
• Breaking: arguments of live_viewer.LiveViewer after port are keyword-only.
• Breaking: removed the deprecated Technology.connections attribute and connections argument of Technology (use Technology.connected_layers), the arguments bend90 and bend90_cost of parametric.route_auto (use bend and bend_cost), and the from_bytes class methods of the built-in models.

1.6.0 - 2026-10-12

Added

• Schematic editing in live_viewer.LiveViewer: place, move, wire and route components in the Schematic view or on the layout, with undo and redo.
• The LiveViewer’s DRC section runs KLayout or Calibre DRC on the design on screen and draws the markers of any KLayout or Calibre report on the layout.
• drc_check and lvs_check run DRC and LVS on a component or layout file. See Layout Verification.
• load_drc_results and load_lvs_results read an existing results database.
• config.default_drc_lvs_engine sets the default DRC/LVS engine.
• config.klayout_executable and config.calibre_executable to select the KLayout and Siemens Calibre executables used by DRC/LVS checks.
• parametric.route_electrical for automatic routing of electrical connections, with vias, bundles and optional 45° tracks.
• LayerSpec.min_width and LayerSpec.min_spacing design rules, used as defaults by parametric.route_electrical.
• AnalyticWaveguideModel.nonlinear builds a nonlinear waveguide model (Kerr effect, two-photon absorption and free carriers) from physical parameters, the medium’s nonlinear specification, or a port mode solve.
• Arguments sections, peak_power, max_phase and dn_fc_map in AnalyticWaveguideTimeStepper for split-step simulation of nonlinear waveguides.
• PolarizationModeDispersionTimeStepper, used by abstract.pmd_fiber in time-domain simulations instead of a pole-residue fit.
• Argument dual_polarization in abstract.fiber, for fibers that carry both polarizations and connect to abstract.pmd_fiber. AnalyticWaveguideTimeStepper now supports multi-mode ports.
• PDA traceability: pda.Project.version_history, pda.Project.trace, pda.Project.attachment_status, pda.Project.tree and pda.Project.traceability_matrix relate attached files to the component versions they describe, and pda.Project.add_version tags attachments with the new version.
• PDA edit history: pda.Project.edit_log, pda.Project.latest_head, pda.Project.changed_since and pda.Project.watch, and argument save in pda.Project.load and pda.Project.component to load a design as it was after any save.
• pda.restore_project and pda.Project.restore to recover retired projects, components and technologies.
• Attachments on technologies in PDA projects, and argument search in pda.Project.attachments.
• Experimental dataset pointers in PDA projects: pda.Project.attach_query, pda.Project.load_query and pda.Project.run_query.

Changed

• Breaking: live_viewer.LiveViewer listens on 127.0.0.1 by default. To reach it from another machine, use an SSH tunnel or the new host and allowed_hosts arguments. Creating a viewer again on the same port replaces the previous one.
• Breaking: Abstract Components are drawn in the layout as their schematic symbols, which changes their size and port positions.
• Faster time-domain simulations: built-in time steppers run in native code, and CircuitTimeStepper can compile circuits with numba (install the numba extra; see config.compile_circuit_time_steppers). Results can differ slightly from previous versions: loops without delay are solved with Newton’s method, and noise samples differ for the same seed.
• PhotonForge settings are kept in tidy3d’s configuration under [plugins.photonforge], where they can be saved and overridden with TIDY3D_PLUGINS__PHOTONFORGE__<NAME> environment variables. Setting remote_logging = false there stops sending usage data (see Privacy and Usage Data).
• SVG previews of virtual nets draw dashed lines only between members not yet connected by metal.

Fixed

• Tidy3DModel.batch_data no longer returns an empty batch when the Tidy3D local cache is disabled or cold. Tasks without a local copy are resolved through their own ids and downloaded when the data is accessed.
• pda.list_libraries failing for accounts with access to many projects.
• Adding the first component to an empty PDA project.
• Saving from the PDA GUI no longer drops a component’s own geometry, ports and models.
• SVG previews showing the wrong geometry for different components that share a PDA id, such as two versions of one component.
• BraggGratingModel.bragg_wavelength includes dispersion when solving the Bragg condition, and accepts an interpolated effective index without a reference frequency.
• Dispersion in AnalyticWaveguideTimeStepper and abstract.fiber no longer attenuates signals near the edges of the simulation band.
• Breaking: signs that did not follow the $e^{-i\omega t}$ time convention. frequency in OpticalPulseTimeStepper placed the pulse on the wrong side of the carrier, and a positive chirp gave a down-chirp instead of an up-chirp. A positive chirp in ElectroAbsorptionModTimeStepper, AnalyticWaveguideModel and AmplitudeModTimeStepper red-shifted the rising edge; it now blue-shifts it, as datasheet values expect. Results change only for nonzero values of these arguments.
• EMEModel failing on components with a FiberPort.
• CircuitModel failing on unrotated references to components with a FiberPort.
• Entries in config.default_kwargs for a parametric function, such as "bend", were passed to other functions, such as the routers, as the argument with the same name.
• Argument turns of parametric.circular_spiral was shown with length units in parameter forms.

1.5.4 - 2026-09-21

Added

• New models BraggGratingModel (guide) and PolarizationModeDispersionModel.
• New time steppers SemiconductorAmplifierTimeStepper, AvalanchePhotodiodeTimeStepper, and ElectroAbsorptionModTimeStepper.
• New abstract components abstract.avalanche_photodiode, abstract.fiber, abstract.pmd_fiber, abstract.awg, abstract.semiconductor_amplifier, abstract.electro_absorption_modulator, abstract.bragg_grating, abstract.nonlinear_ring, and abstract.vcsel.
• Utility functions franz_keldysh_absorption, saturation_output_power, dispersion_from_beta2, srh_lifetime, and miller_gain.
• LayerSpec.conductive and LayerSpec.device_marker, used for connectivity extraction.
• Lumped-element circuit solving in CircuitModel: references joined by terminal connections are assembled into a single MNA system, solved, and composed with the surrounding wave network.
• Electrical connectivity extraction from layout geometry through Component.extract_connectivity.
• Component.add_virtual_net, Component.remove_virtual_net, Component.remove_virtual_net_member, and Component.virtual_nets to declare electrical nets.
• Virtual net support in component_from_netlist.
• Batch mode-solving support in port_modes.
• Path-length matching for existing routes through match_path_lengths, specified per group by PathLengthMatching: geometric length, optical phase, or group delay, matched to explicit targets or to the longest net in the group, with per-net length offsets, bend-count contracts, and a spacing floor.
• Argument matching in parametric.route_auto, which matches groups on the routed paths, before any geometry is emitted.
• Arguments length and length_tolerance in parametric.route, for a single route meandered to an exact geometric length.
• Argument group_index in effective_route_length, to build the index from group indices and measure group delay instead of phase.
• TimeStepper.write_verilog_a as a simpler interface replacing the experimental spice module (guide).
• fiber module with helpers for fiber model design.

Changed

• Component.get_netlist lists the physical and the virtual N-way MNA nodes.
• Conversion to SPICE raises an error on hierarchies that use terminal connections, which it cannot represent.
• GDSII readers warn and skip on malformed data that is not geometry-related. Geometry-related errors remain fatal.

Fixed

• Argument metal_layer of basic_technology was ignored, and its value was never validated.
• Layer names in Technology.connections are now resolved against the technology being created or configured, instead of the default technology.
• Call-time technology updates in Reference.update now chain to the referenced component.
• abstract.ring_resonator now passes the complex coupling factors to its time stepper instead of magnitude only.

1.5.3 - 2026-08-26

Changed

• Made the new layout readers (for GDSII and OASIS files) more lenient with degenerate structures.

1.5.2 - 2026-08-21

Added

• Support for transformed Reference arrays (columns > 1 or rows > 1).
• Automatic notebook updates in live_viewer.LiveViewer after successful cell execution in Jupyter notebooks/IPython.
• Support for file attachments on individual PDA components.
• spice module for generating SPICE models and converting components to Verilog-A. Removed in 1.5.4 in favour of TimeStepper.write_verilog_a.

Changed

• Breaking: changed defaults on parametric.route_auto for better performance. The grid size now defaults to half the routing radius, and collision checks default to the layers used by the routed waveguide.
• Improved accuracy for extrusions with sidewall angles.
• Improved memory usage on GDSII and OASIS reading and writing.
• Improved live_viewer.LiveViewer performance and responsiveness for large layouts, hierarchy filtering, and raster rendering.
• Local mode-solving (config.use_local_mode_solver) available only when subpixel is enabled in tidy3d-extras package to guarantee accuracy.
• Documented that DelayedTimeStepper quantizes delays down to whole time steps.

Fixed

• PhotodiodeTimeStepper shot noise now follows the instantaneous space-charge-limited photocurrent by default, independent of the simulation time step.
• RingTimeStepper now rejects non-unitary coupling coefficients during construction.
• ElectricalAmplifierTimeStepper compression_power and ip3 handling to correctly apply to real tones.
• OpticalPulseTimeStepper relative intensity noise now applies to optical power instead of field amplitude.
• Reflection coefficient no longer ignored in OpticalPulseTimeStepper.
• DMLaserTimeStepper relative intensity noise application independent of time step.
• Corrected bend, S-bend, and crossing costs in parametric.route_auto, including off-grid component access, and improved 45-degree bend normalization and collision protection.
• Improved network connection robustness for PDA.

1.5.1 - 2026-07-16

Added

• Cross-section visualization tool for live_viewer.LiveViewer.
• Argument reference_frequency to RingTimeStepper, PhaseModTimeStepper, and TerminatedModTimeStepper, as well as their corresponding Abstract Components.
• Added carrier-aware rebasing and mode-key validation for explicit pole-residue matrices.

Changed

• The default abstract.phase_modulator now includes dispersion introduced by a non-zero value of n_group, aligning it to the default behavior of other Abstract Components.
• MuxDemuxModel now uses causal Butterworth filters with integer order and constant reflections.
• Port names now use natural ordering across models and time steppers (P9 before P10).
• photonforge-server --example will use the latest compatible Abstract Component Library it finds, instead of raising an error if the exact version is not found.

Fixed

• Bug in pda.Project.add_library not working when library name is not unique.
• Bug in pda.Project producing an error whenever a model or component schema is upgraded.
• Bug in PDA using the wrong library name for projects that were renamed after being versioned.
• Bug in delay buffers using the wrong value until the delay was reached, making the result of CircuitTimeStepper order-dependent in certain situations.
• pole_residue_fit not providing a clear error or warning when the requested number of poles is above the limit in certain cases.
• Bug in load_snp preventing files to load properly when frequency points were scaled.
• Bug in serialization of bytes objects in phf files.
• Model copies not including customized TimeStepper.

1.5.0 - 2026-07-08

Added

• parametric.route_auto for automatic bundle routing with collision detection and crossing insertion.
• parametric.route_u, parametric.route_z, parametric.route_l for simple routing of parallel port bundles.
• routing_collisions to check for collisisons in routing.
• Argument endpoint to parametric.straight to allow precise diagonal segments to be built without having to rotate them.
• Support for automatic selection of geometry or permittivity-based automatic differentiation in Tidy3DModel.

Changed

• More robust parametric component name hashing.
• Changed the name of the default cladding material in basic_technology to "Palik_LowLoss" because "Palik_LossLess" is deprecated in Tidy3d.

Fixed

• Incorrect duplicate name error when adding or updating routes in PDA projects.
• Missing degrees to radians conversion factor in phase_bias for MZMTimeStepper.
• Default return loss of a few Abstract Components to ensure passivity.

1.4.7 - 2026-06-25

Added

• Argument carrier_frequency to SMatrixTimeStepper and smarter selection of electrical or optical model when time-stepping circuits.

Changed

• Improved the robustness of DirectionalCouplerCircuitModel.
• Improved performance of simulations in photonforge-server.

Fixed

• Bug in photonforge-server preventing use of read-only libraries.

1.4.6 - 2026-06-22

Added

• pda.Project.attach, pda.Project.detach, pda.Project.attachments, and pda.Project.download_attachment to work with file attachments in PDA projects.
• Support for permittivity-based automatic differentiation and adjoint optimization of parametric components.

Changed

• Performance improvements in the PDA system for storing and loading large projects or libraries.

Fixed

• Bug in Component.get_netlist that provoked a segfault when a warning would be issued for a disconnected 3D port.
• Bug in monte_carlo.s_matrix not reporting correct errors on simulation failures.

1.4.5 - 2026-06-15

Added

• Time-domain simulation support for built-in lumped elements.

Changed

• Increased timeout for finding and retrieving PDA documents to better accpunt for connection problems.

Fixed

• Fix time-dependent term sign in all LumpedModel to be compatible with the Tidy3d convention $e^{-i\omega t}$.
• Removed the connection limit for the PDA client to handle larger data payloads.

1.4.4 - 2026-06-10

Added

• Support for Tidy3d’s automatic differentiation and adjoint optimization with parametric components.

Changed

• Added the flexibility of specifying the phase of the coupling coefficient in the RingTimeStepper.
• Improved live_viewer.LiveViewer: faster rendering, support for large layouts (millions of shapes), shape-snapping ruler, geometry culling by layer, cell or hierarchy depth.

Fixed

• Bug in photonforge-server not resolving required parameters correctly from all referenced components.
• Bug in pda.Project.add_library ignoring the selected library version and always using latest.

1.4.3 - 2026-05-27

Added

• pda.Project.list_tags and pda.Project.list_versions to list tags and versions for the project or its contents.
• pda.Project.retire_unused to automatically clean up unused internal components in the project.
• pda.Project.is_read_only to query the read/write state of a loaded project.
• Argument external_only to pda.Project.components to filter returned results.

Changed

• More performance improvements to the PDA system and photonforge-server.
• Breaking: pda.Project.reload renamed to pda.Project.load_latest.

Fixed

• Bug in analytic models not using the provided reference frequency to compute dispersion.
• PDA projects are loaded at specific versions or tags as read-only.
• PDA incompatibility with python < 3.12.
• Bug in PDA projects preventing custom modules to be saved in certain scenarios.
• Bug in deep copying objects with cyclic dependencies through parametric keyword arguments.

1.4.2 - 2026-05-12

Changed

• Performance improvements to the PDA system and photonforge-server when loading projects or adding libraries.

1.4.1 - 2026-05-10

Fixed

• Bug on the photonforge-server that prevented parametric components to be updated after copy and paste.

1.4.0 - 2026-05-08

Added

• Photonic Design Automation (PDA) support.
• Abstract component library: Abstract Components.
• LumpedModel to support compact models for lumped elements, and Capacitor, IdealTransformer, IdealTransmissionLine, Inductor, ParallelRLC, Resistor, SeriesRLC.
• New result and support classes ZMatrix, YMatrix, MNAMatrix.
• New models: CirculatorModel, IsolatorModel, MuxDemuxModel, RingModel, and DualRingModel.
• New time steppers: MZMTimeStepper, AmplitudeModTimeStepper, and RingTimeStepper.
• effective_route_length to compute the effective length of waveguides.
• Polygon.fillet for rounding polygon corners.
• Technology.extrusion_layers, ExtrusionSpec.mask_layers, and MaskSpec.get_layers.
• Model.transform that can be specialized to transform models that have any spatial dependency.
• Component.active_model_name to retrieve the name of the currently active model(s).
• Extended Interpolator to handle multi-dimensional interpolation and constant extrapolation.
• Trimming arguments to offset.
• Argument include_labels to bounds and convex hull computations for components and references.
• Argument layers to Component.bounds and Component.convex_hull.
• Argument bit_sequence to WaveformTimeStepper to allow custom bit sequences to be used.
• Arguments grid and multiple to snap_to_grid, grid_floor, and grid_ceil.
• Argument suppress_warnings to Component.get_netlist.

Changed

• Improved parametric function naming scheme to avoid using hashes too frequently.
• Simplified handling of butt-coupling connections that internally use an EMEModel.
• Component extrusion uses ConstructiveSolid to merge structures with common media.
• Coordinate snapping on parametric components is more robust to most numerical inaccuracy sources.
• SVG representations make use hatching patterns defined in LayerSpec.
• Breaking: Argument change in PhaseModTimeStepper: tau_rc was replaced by a more convenient f_3dB.

Fixed

• Component.update affecting the wrong component through caching.
• Path.bezier bug that prevented high order bezier curves from working.
• Handle circuits with both electrical and optical connections that require phase corrections simultaneously.
• Improved automatic extrusion tolerance for RF ports with self-intersecting geometries.
• n_group2 precedence in AnalyticMZIModel
• Circuit simulations with transformed sub-components and user-defined bounds are now correctly transformed.
• Bug in TerminatedModTimeStepper affecting cases where the source was not matched to the modulator’s characteristic impedance.
• Energy conservation bug in PhotodiodeTimeStepper when a reflection coefficient was used.

1.3.2 - 2026-02-04

Added

• New time steppers: AnalyticWaveguideTimeStepper, FilterTimeStepper, OpticalAmplifierTimeStepper, ElectricalAmplifierTimeStepper, ExpressionTimeStepper, DifferentialTimeStepper, IntegralTimeStepper.
• New model DirectionalCouplerCircuitModel, used as new default for parametric directional couplers.
• Argument in Component.get_netlist to ignore virtual connections. Useful for checking layout-only connections.

Changed

• WaveguideModel has increased phase accuracy for bends by accounting for polarization rotations between ports.
• route_length was improved to work with multi-path waveguides, like CPW transmission lines.

Fixed

• Breaking: EMEModel compatibility fix for Tidy3d 2.10.2 (EMEModels created with Tidy3d 2.10.1 and PhotonForge 1.3.0 and 1.3.1 will be incompatible with this and future releases due to a schema change in Tidy3d.).
• Bug in Tidy3DModel when simulating a small region inside a large component that affected extended ports.
• Bug in parametric.route_taper when both terminal structures were 1-dimensional and orthogonal.
• Invalid Euler bend parameters now raise proper error.
• Division by zero in some waveguide models when vpi_L was set to 0.
• Division by zero error in empty circuits.

1.3.1 - 2026-01-14

Fixed

• SVG previews no rendering the correct colors.

1.3.0 - 2026-01-14

Added

• Support for connections between ports with different profiles in Component.get_netlist, bridged through EME or an impedance mismatch model in circuits.
• PortSpec.impedance to be used on electrical ports to pre-define the port impedance.
• Terminated phase modulator time stepper TerminatedModTimeStepper
• Argument post_load_function to load_layout to help automating port/pin detection when loading layout files.

Changed

• Breaking: classes derived from TimeStepper require a keys attribute or property, and the interface for TimeStepper.step_single uses arrays instead of dictionaries for improved performance. Custom user-defined time steppers will have to be manually updated.
• Impedance argument z0 controls the conversion between wave amplitudes and voltages/currents in DMLaserTimeStepper and PhotodiodeTimeStepper

Fixed

• Handling of pre_export_function in write_layout.
• PhotodiodeTimeStepper bug when using saturation current (undefined variable).

1.2.3 - 2025-12-19

Fixed

• CWLaserTimeStepper and DMLaserTimeStepper phase signs.

1.2.2 - 2025-12-12

Added

• Interpolator to be used when certain class arguments must be defined as interpolated values.
• config.svg_reference_depth replaces the now deprecated config.svg_references to give more fine-grained control over reference display in SVG previews.
• Support for transforming empty paths into polygons when their end caps allow it.

Changed

• New parametric component arguments for setting models. Old “kwargs” style parameters have been deprecated.
• Improved performance of CircuitTimeStepper.
• Better default model naming.

Fixed

• Removed unused arguments show_progress and model_kwargs from plot_s_matrix.

1.2.1 - 2025-11-13

Added

• OpticalPulseTimeStepper and OpticalNoiseTimeStepper.

Fixed

• Bug in CircuitTimeStepper when using rotated references.
• Warning message bug in SMatrixTimeStepper.
• live_viewer.LiveViewer not properly displaying images after server update.

1.2.0 - 2025-11-12

Added

• Time-stepping functionality for single components and circuits using the new classes CircuitTimeStepper, SMatrixTimeStepper, DelayedTimeStepper, PhaseModTimeStepper, CWLaserTimeStepper, DMLaserTimeStepper, WaveformTimeStepper, PhotodiodeTimeStepper (subclasses of TimeStepper), and TimeSeries.
• New model classes: AnalyticDirectionalCouplerModel, AnalyticMZIModel, AnalyticWaveguideModel, CrossingModel, PolarizationBeamSplitterModel, and PolarizationSplitterRotatorModel.
• Component.replace_technology to replace technologies on the component and its dependencies.
• Component.rename_port, Component.rename_terminal, and Component.rename_model to rename existing ports, terminals, and models, respectively.
• Component.center and Reference.center to get entity centers.
• stencil.apodized_grating and stencil.apodized_focused_grating for creation of apodized gratings based on lists of teeth widths and gaps.
• Model.estimate_cost allows cost estimation for any models that support it, including CircuitModel.
• Terminals are now exported from Component.get_netlist, in a similar fashion to ports.
• Added “active models” key to the netlist accepted by component_from_netlist to enable setting separate active models for optical and electrical frequency ranges.
• SMatrix.force_symmetric to make an S matrix symmetric by construction.
• Convenience argument and attribute GaussianPort.waist_distance to align with the definition of Tidy3D’s GaussianBeam.
• Properties.get to retrieve a value with a default fallback.

Changed

• LayerSpec will be assigned a random color and pattern when none are specified.
• Fix for translation of Gaussian source w.r.t. their field monitor, improving reciprocity of results.
• Model.start implementations can return an SMatrix instance directly. Class ModelResult has been deprecated.
• Tidy3DModel.batch_data replace the now deprecated data_path_for, batch_file_for, and batch_data_for.
• EMEModel.simulation_data replace the now deprecated data_path_for, data_file_for, and simulation_data_for.

Fixed

• Bug in basic_technology parsing arguments top_medium and substrate_medium.

1.1.7 - 2025-07-23

Fixed

• Error in PHF storage for Path.

1.1.6 - 2025-07-08

Added

• Argument use_angle_rotation to Tidy3D conversion functions from Port and FiberPort, to enamble angle_rotation in the ModeSpec they generate, if necessary.

Changed

• Mode fields are only stored in Tidy3d simulation data when needed for mode remapping.

Fixed

• Critical error in annotated types from parametric component library (unhashable types).

1.1.5 - 2025-06-24

Added

• PortSpec.default_radius can be used to set preferred radius for any port specification.
• Interpolation method "poleresidue" to DataModel to use a pole-residue matrix fit for frequency interpolations.
• Argument pre_export_function to write_layout, Component.write_gds, and Component.write_oas to make temporary changes in components right before exporting.
• Rectangle.perimeter, Circle.perimeter, Polygon.perimeter, and Path.perimeter for perimeter computation.
• Properties to all objects to hold arbitrary metadata.
• Argument min_evals to Circle and Path section methods to override the minimal number of points used in polygonal conversion based on config.tolerance.
• Argument max_evals to Path section methods to allow the construction of complex geometries that require more evaluations that the default.
• PortSpec.path_profiles_list to get path profiles always as a list.

Changed

• Deprecation: All json methods have been deprecated for removal in the 1.2 release.

Fixed

• Memory access bug in S matrix comparison.
• Other minor memory leak fixes.

1.1.4 - 2025-05-03

Added

• Component.slice_profile to create path profiles from existing waveguide geometries.
• ExtrusionSpec.reference to change the reference plane for sidewall angle dilations and erosions.
• MaskSpec.translation to allow masks to be translated during extrusion (mainly for mask alignment sensitivity tests).
• Support for SubpixelSpec to Tidy3DModel and EMEModel.
• Helper function virtual_port_spec to quickly create virtual port specifications.

Changed

• WaveguideModel now accepts a PortSpec or the string "cross-section" for more flexible propagation index calculation.
• Updated minimal config.grid size to avoid truncation errors when snapping ports.
• Updated default settings for electrical simulations (experimental feature).
• Updated default values for electrical simulation grids and cpw_spec.

Fixed

• parametric.rectangular_spiral length incorrectly calculated in specific cases.
• Serialization of complex Tidy3D objects included in a Tidy3DModel.
• Improved error handling in a few python interfaces.
• Segfault in Path.bezier.

1.1.3 - 2025-04-11

Added

• Support for angled ports in circuit simulations.
• Several Path attributes.
• Path.interpolate to query path positions by length.
• Path.updated_copy to create copies with different widths and offsets.
• ExtrusionTable and PortSpecTable visualizers, used by default with Technology.extrusion_specs and Technology.ports.
• Better console and HTML representations for Technology.
• Support for ports in curved waveguides with Port.bend_radius.

Fixed

• Backwards compatibility fix in phf files using specific parametric technologies.

1.1.2 - 2025-03-25

Fixed

• Crash when no active model is present in phf file.

1.1.1 - 2025-03-24

Added

• Terminal routes in component_from_netlist accepts keyword arguments.
• Component.query and Reference.query to look for ports and terminals within the component dependency tree.
• Arguments boundary_margin and minimal_turn_angle to Component.detect_ports to fine-tune port detection
• grid_layout to arrange components or other structures in a rectangular grid.
• pack_layout to pack components or other structures in a compact area.
• Support for specifying waypoints as 2D coordinates in parametric.route_manhattan.

Changed

• Analytical models include all-zero elements in S matrix output.

Fixed

• Tidy3D simulation hanging when an error occurs during upload or download.
• Axis label in plot_s_matrix.
• Component.detect_ports properly detects and ignores co-linear vertices in polygons.
• Data arrays from numpy and xarray within Tidy3D objects breaking serialization.

1.1.0 - 2025-03-04

Added

• Electrical interface support: electrical port specifications and terminals, terminal routing with parametric.route_taper, and parametric.route_manhattan and cpw_spec utility function to create CPW port specifications.
• Class TimeDomainModel for time-stepping based on a PoleResidueMatrix.
• live_viewer.LiveViewer for live geometry and component visualization.
• Functions PoleResidueMatrix.is_passive, PoleResidueMatrix.enforce_passivity, and PoleResidueMatrix.get_rms_error.
• Options passive, delays, stable, and feedthrough in pole_residue_fit to better control the fitting process.
• parametric.circular_spiral as an alternative to existing rectangular spiral.
• Argument full_length to parametric.rectangular_spiral and parametric.circular_spiral to preset the desired spiral length.
• FDTD cost estimation with Tidy3DModel.estimate_cost.
• Defaults for parametric components and models can be set in config.default_kwargs.
• Path.arc, Path.turn, and Path.s_bend can use defaults for radius and euler_fraction from config.default_kwargs.
• Function s_bend_length can be used to calculate the ideal S bend length for specific radius and offset.
• Component.size and Reference.size.
• Terminal.center and Terminal.size.
• Subscript operation to Component to retrieve ports and terminals.
• Component.disconnected_reference_ports and Component.add_reference_ports to facilitate adding ports from references.
• Component.tree_view to pretty-print component dependency trees.
• Parameter on_boundary to Component.detect_ports to limit search at the component boundaries.
• Function heal to remove small features from structures.
• Added bulge option to automatically widen long straight waveguide sections.
• config.svg_reference_labels to control display of labels from references.
• Json representation for planar structures.
• Class FiberPort for general waveguide ports.
• Port.can_connect_to verifies if 2 ports can be connected by a waveguide route.
• PortSpec.combined_with to combine path profiles from port specifications.
• PortSpec.added_solver_modes to port specifications, which allows for single TM mode ports.
• Attribute MaskSpec.layer for single-layer mask specifications.
• LayerTable visualizer for technology layer specifications, used by default with Technology.layers.
• Argument verbose to Tidy3DModel.start, EMEModel.start, WaveguideModel.start, and CircuitModel.start.
• Accept simplified forms of port symmetries and added Tidy3DModel.test_port_symmetries.
• abort_pending_tasks can be used to abort all running simulations at once.
• Function SMatrix.estimate_phase for estimation of minimum-phase-shift data from given amplitude data, and functions SMatrix.apply_time_delay and SMatrix.estimate_delays.
• Function port_modes to solve port modes using caches.
• Argument parallel_jobs to start multiple Monte Carlo tasks in parallel in monte_carlo.s_matrix.

Changed

• Parallel upload and download of Tidy3D tasks.
• Default run_time quality factor changed from 10 to 5 in order to decrease the default estimated cost of Tidy3D runs.
• Use default precision in mode solver.
• Remove out-of bounds structures from simulations to avoid Tidy3D warnings.
• Where available, default keyword arguments for parametric components and technologies are included in Component.parametric_kwargs and Technology.parametric_kwargs.

Fixed

• Bug in MaskSpec comparison.
• Do not create complex geometry with more than 100 sub-geometries to avoid errors in Tidy3D.
• Vernier scale stencil bug fix to generate proper geometry.
• Support for numpy complex scalars in phf streams.
• Better HTML escaping in SVG representations.
• Improved Tidy3D object conversion to include spatial data arrays in runtime caches.
• Port mode numbering for S matrices is consistent with and without setting PortSpec.polarization.
• Bug in error handling within paths.

1.0.5 - 2025-01-02

Added

• Attribute _id for internal use.
• Configuration option config.svg_label_scaling.

Changed

• More robust guarantees for gradients for path endpoints.
• Paths are stored as polygons by default in GDSII and OASIS files.
• Reference.component can be set.
• Simplified updates argument in CircuitModel.start.

Fixed

• Path alignment fixes for parametric couplers.
• Minor docstring fixes.

1.0.4 - 2024-11-21

Added

• Complex vector fitting for baseband signals via pole_residue_fit with real=False.

Changed

• Sign convention for the frequency variable in PoleResidueMatrix.
• In pole_residue_fit, min_poles and max_poles now count a single conjugate pair as two poles.
• S matrices store all-zeros instead of dropping them.
• Routes can be specified by reference and port name to facilitate updating if the reference is transformed.

Fixed

• Significant accuracy improvements in pole_residue_fit.
• Component comparison takes ports into account.

1.0.3 - 2024-11-01

Fixed

• Function stencil.as_component takes a technology argument for the created component.
• Apply union to polygons before erosion, as indicated in the documentation.

1.0.2 - 2024-10-25

Added

• Function Tidy3DModel.test_port_symmetries gained a verbose argument to control printed messages.

Changed

• Function tidy3d_plot will use the component’s Tidy3DModel if it has one.

Fixed

• Function Port.to_tidy3d_mode_solver correctly sets the generated group_index_step.
• Tidy3DModel supports 2D simulations when bounds are overridden.

1.0.1 - 2024-10-15

Changed

• Suppress extrusion error message from Tidy3D when falling back to triangular mesh.

Fixed

• Always export paths with round or beveled joins as polygons.
• Forbid inheritance from PhotonForge classes (except Model) because the internal design does not support it.
• Error when parsing arguments in Path.parametric.
• Runtime errors in EMEModel.
• Degenerate port modes are handled correctly when symmetry is used in Tidy3DModel and EMEModel.

1.0.0 - 2024-10-10

Initial release.