Feature Tour

A visual walk through what Phidler can do. If you'd rather build something hands-on, jump to the MZI Tutorial. For the full reference, see the User Guide.

Open or start a project

Launching Phidler opens a recent-projects list. Pick up where you left off, browse for a file, or start fresh (which opens Project Settings to choose a material platform).

The startup dialog listing recent projects with Open Selected, Open Other, and New Project buttons

The workspace

One window holds the whole flow. A searchable component palette sits on the left, the canvas in the middle, and docked Properties, Layers, DRC, and Console panels on the right and bottom. Toolbars across the top carry the place / route / measure tools and the grid, snap, units, export, and simulate controls.

The Phidler main window with a Mach–Zehnder interferometer laid out

Place components

Every gdsfactory PDK (process design kit) component is in the palette, grouped by kind. Type in the filter box to narrow hundreds of factories down to what you want, and hover any entry for a live rendered preview before you place it.

Component palette filtered to 'ring', showing matching couplers, rings, and dies Palette with a hover preview popup showing a rendered thumbnail of the component under the cursor

The catalog is the whole gdsfactory generic PDK, grouped by kind: waveguides, bends, couplers, splitters, rings, gratings, edge couplers, and more.

The component palette with its top categories expanded, showing the grouped PDK catalog

Selecting a placed component opens its full parameter set in the Properties panel: position and orientation, an Array section for tiling, and every gdsfactory factory argument (radius, gap, length, …), edited live.

Properties panel for a ring resonator showing transform, array, and component parameter fields

Edit on the canvas

Drag to move, grab the on-canvas handles to rotate and scale, or type exact values into Properties. A right-click gives you rotate, flip, align, copy, delete, and zoom. They're all on the Edit menu too, with keyboard shortcuts.

A selected bend with on-canvas transform handles for rotation and scaling The right-click canvas context menu listing rotate, flip, align, copy, delete, and zoom actions

Select several components at once to move them as a group, or line them up and space them evenly with the Align and Distribute tools.

Two components selected together on the canvas

Align snaps a selection to a shared edge or centre:

Three splitters aligned to a common top edge

…and Distribute spaces three or more evenly:

Three ring resonators spaced evenly after Distribute Horizontally

A background grid keeps things tidy. With Snap on, placement, dragging, and routing all round to the grid pitch you set.

A close-up of the canvas grid with a waveguide port snapped to a grid intersection

Array a component

Need a fiber array, a bank of rings, or a splitter tree? Set columns, rows, and pitch in the Array section and Phidler tiles the component as a single unit.

A vertical grating-coupler array placed as one arrayed instance

Route between ports

Click a port, then another, and Phidler draws a waveguide between them. Pick the cross-section the route is drawn with, and route with all-angle diagonal bends or Manhattan. Here's the good part: set a goal length and let Phidler insert an adiabatic meander to hit it, so matched delays come for free.

Routing mode: hovering a port with the rubber-band preview tracking to the target

The cross-section dropdown open, listing strip, rib, nitride, and other PDK cross-sections

Select a route to read back its exact length and propagation time, including how far it lands from your goal.

An MZI with a meandered, length-matched lower arm and the route length readout

Measure

The measure tool reports the distance between any two points, snapping to nearby ports, with a dimension annotation right on the canvas.

The measure tool showing the distance between two ports with an on-canvas dimension line

Distance or delay

Switch the Units control from microns to propagation time and the rulers and readouts re-express length as time-of-flight (fs / ns), using the effective index from your last mode solve. It's the view that matters when you're budgeting delays.

The canvas rulers labelled in femtoseconds of propagation time instead of microns

Layers

The Layers panel lists every layer actually used by your design, with a visibility toggle and an editable colour per layer.

The Layers panel listing waveguide, slab, metal, and via layers with visibility toggles and colour swatches

Trace over a reference

Import an existing GDS as a dimmed, non-editable backdrop and lay your design over it. Handy for matching an existing chip or a supplied floorplan.

A new waveguide being drawn over a dimmed reference-GDS ring resonator

Check design rules

A quick DRC checks minimum width and spacing on a chosen layer and lists the violations; click one to zoom straight to it on the canvas.

The DRC panel with min-width and min-spacing controls and a flagged violation A DRC width violation highlighted in red on the canvas

Simulate with FDTD

Phidler ships a real FDTD engine (finite-difference time-domain, the workhorse method for simulating how light moves through a structure). Start with the vertical mode profile: solve the guided mode of your waveguide cross-section and see its field and effective index.

The FDTD mode-profile tab showing the solved guided mode field

Then place sources on the canvas (a plain dipole, a mode-matched single photon, a scripted waveform, or a Cherenkov track), pick the cladding material, choose CPU/Numba/GPU, and run.

The FDTD propagation controls with two sources placed in the source table The source-kind dropdown listing dipole, single_photon, scripted, and cherenkov The cladding-material dropdown listing SiO2, air, Si3N4, and other presets

Watch the pulse propagate through your actual layout, scrub the field movie frame by frame, and export it as an animated GIF.

An FDTD propagation snapshot: a pulse mid-flight along a waveguide, with playback controls

Runs too big for your laptop? Offload to a GPU (NVIDIA CUDA or AMD ROCm) or to a remote server over SSH. The progress bar and results come back the same either way.

The remote-server configuration dialog with host alias, remote directory, Python path, and a GPU toggle

Script it when you want to

For anything the UI doesn't cover, a scripting console runs Python against the live session with gf, the document, and place()/route() helpers. Mix clicking and code freely.

The scripting console placing and routing components against the live session

Or just ask Claude

Don't feel like clicking or writing code? Switch the Console to Ask Claude and describe what you want — "add a 2×2 MMI and route both outputs to the grating couplers." Claude builds it on the live canvas through the same session the console uses, so you watch every edit land (and it reads whatever you've got selected, so "route these two" works). It's optional: you need the ai extra and the Claude Code CLI installed.

What you can build

From a single waveguide to a full circuit: splitters and combiners, ring resonators and add–drop filters, fiber-coupler arrays, delay lines, and interferometers. Lay it out visually and export it as GDS.

A clean add–drop ring resonator laid out on the canvas

Active devices too. Here's a thermo-optic phase shifter, its metal heater and via stack sitting over the optical waveguide (note the metal layers in the Layers panel).

A straight waveguide with a metal heater and via routing — a thermo-optic phase shifter

Save & export

Projects save to an editable .phidler file that remembers your whole design and simulation set-up. When you're done, export a foundry-ready GDSII, or a Python script that rebuilds the layout in gdsfactory.

The File menu showing New, Open, Save, Import Reference GDS, Import Custom Components, Export GDS, and Export Python Script

Ready to build one yourself? Start the MZI Tutorial »