Broadband Directional Coupler with GDSFactory FDTD¶

Evaluate a phase-controlled directional coupler designed for a flat 50/50 split over a broad wavelength range.

Requirements: GDSFactory+ cloud simulation access.

You will: build the component, configure the solver, preview the 3D setup, run one cached cloud simulation, and inspect its wavelength response.

1. Build the component¶

import gdsfactory as gf

from gsim import fdtd

gf.gpdk.PDK.activate()
component = gf.components.coupler_broadband(
    radius=5.0,
    bend="bend_circular",
)
component

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png

2. Configure the simulation¶

simulation = fdtd.Simulation()
simulation.materials(background="SiO2", overrides={"si": 3.4757})
simulation.geometry(component)
simulation.source(
    port="o1",
    wavelength_um=1.55,
    wavelength_span_um=0.1,
    num_wavelengths=101,
)
simulation.domain(padding_um=1)
simulation.solver(cell_size_nm=60, energy_decay_fraction=1e-5)

Solver(cell_size_nm=60.0, max_timesteps=None, energy_decay_fraction=1e-05, max_wall_seconds=3600.0)

Preview the resolved layer stack, ports, and simulation domain before submitting the job.

simulation.plot_3d()

3. Run and inspect the result¶

result = simulation.run(check_cache=True)

  fdtd-3d72489f  [####################] 100%  complete  elapsed 9m 44s


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result.s_parameters.plot_plotly()