tidy3d.plugins.waveguide.RectangularDielectric

class RectangularDielectric

Bases: Tidy3dBaseModel

General rectangular dielectric waveguide

Parameters:

• wavelength (Attribute: wavelength) –

  Type	Union[float, ArrayLike[dtype=float, ndim=1]]
  Default
  Units	um
  Description	Wavelength(s) at which to calculate modes (in μm).

• core_width (Attribute: core_width) –

  Type	Union[NonNegativeFloat, ArrayLike[dtype=float, ndim=1]]
  Default
  Units	um
  Description	Core width at the top of the waveguide. If set to an array, defines the widths of adjacent waveguides.

• core_thickness (Attribute: core_thickness) –

  Type	NonNegativeFloat
  Default
  Units	um
  Description	Thickness of the core layer.

• core_medium (Attribute: core_medium) –

  Type	Union[Medium, AnisotropicMedium, PECMedium, PoleResidue, Sellmeier, Lorentz, Debye, Drude, FullyAnisotropicMedium, CustomMedium, CustomPoleResidue, CustomSellmeier, CustomLorentz, CustomDebye, CustomDrude, CustomAnisotropicMedium, PerturbationMedium, PerturbationPoleResidue, Medium2D]
  Default
  Description	Medium associated with the core layer.

• clad_medium (Attribute: clad_medium) –

  Type	Union[Medium, AnisotropicMedium, PECMedium, PoleResidue, Sellmeier, Lorentz, Debye, Drude, FullyAnisotropicMedium, CustomMedium, CustomPoleResidue, CustomSellmeier, CustomLorentz, CustomDebye, CustomDrude, CustomAnisotropicMedium, PerturbationMedium, PerturbationPoleResidue, Medium2D]
  Default
  Description	Medium associated with the upper cladding layer.

• box_medium (Attribute: box_medium) –

  Type	Union[Medium, AnisotropicMedium, PECMedium, PoleResidue, Sellmeier, Lorentz, Debye, Drude, FullyAnisotropicMedium, CustomMedium, CustomPoleResidue, CustomSellmeier, CustomLorentz, CustomDebye, CustomDrude, CustomAnisotropicMedium, PerturbationMedium, PerturbationPoleResidue, Medium2D]
  Default	= None
  Description	Medium associated with the lower cladding layer.

• slab_thickness (Attribute: slab_thickness) –

  Type	NonNegativeFloat
  Default	= 0.0
  Units	um
  Description	Thickness of the slab for rib geometry.

• clad_thickness (Attribute: clad_thickness) –

  Type	Optional[NonNegativeFloat]
  Default	= None
  Units	um
  Description	Domain size above the core layer.

• box_thickness (Attribute: box_thickness) –

  Type	Optional[NonNegativeFloat]
  Default	= None
  Units	um
  Description	Domain size below the core layer.

• side_margin (Attribute: side_margin) –

  Type	Optional[NonNegativeFloat]
  Default	= None
  Units	um
  Description	Domain size to the sides of the waveguide core.

• sidewall_angle (Attribute: sidewall_angle) –

  Type	float
  Default	= 0.0
  Units	rad
  Description	Angle of the core sidewalls measured from the vertical direction (in radians). Positive (negative) values create waveguides with bases wider (narrower) than their tops.

• gap (Attribute: gap) –

  Type	Union[float, ArrayLike[dtype=float, ndim=1]]
  Default	= 0.0
  Units	um
  Description	Distance between adjacent waveguides, measured at the top core edges. An array can be used to define one gap per pair of adjacent waveguides.

• sidewall_thickness (Attribute: sidewall_thickness) –

  Type	NonNegativeFloat
  Default	= 0.0
  Units	um
  Description	Sidewall layer thickness (within core).

• sidewall_medium (Attribute: sidewall_medium) –

  Type	Union[Medium, AnisotropicMedium, PECMedium, PoleResidue, Sellmeier, Lorentz, Debye, Drude, FullyAnisotropicMedium, CustomMedium, CustomPoleResidue, CustomSellmeier, CustomLorentz, CustomDebye, CustomDrude, CustomAnisotropicMedium, PerturbationMedium, PerturbationPoleResidue, Medium2D]
  Default	= None
  Description	Medium associated with the sidewall layer to model sidewall losses.

• surface_thickness (Attribute: surface_thickness) –

  Type	NonNegativeFloat
  Default	= 0.0
  Units	um
  Description	Thickness of the surface layers defined on the top of the waveguide and slab regions (if any).

• surface_medium (Attribute: surface_medium) –

  Type	Union[Medium, AnisotropicMedium, PECMedium, PoleResidue, Sellmeier, Lorentz, Debye, Drude, FullyAnisotropicMedium, CustomMedium, CustomPoleResidue, CustomSellmeier, CustomLorentz, CustomDebye, CustomDrude, CustomAnisotropicMedium, PerturbationMedium, PerturbationPoleResidue, Medium2D]
  Default	= None
  Description	Medium associated with the surface layer to model surface losses.

• origin (Attribute: origin) –

  Type	Tuple[float, float, float]
  Default	= (0, 0, 0)
  Units	um
  Description	Center of the waveguide geometry. This coordinate represents the base of the waveguides (substrate surface) in the normal axis, and center of the geometry in the remaining axes.

• length (Attribute: length) –

  Type	NonNegativeFloat
  Default	= 1e+30
  Units	um
  Description	Length of the waveguides in the propagation direction

• propagation_axis (Attribute: propagation_axis) –

  Type	Literal[0, 1, 2]
  Default	= 0
  Description	Axis of propagation of the waveguide

• normal_axis (Attribute: normal_axis) –

  Type	Literal[0, 1, 2]
  Default	= 2
  Description	Axis normal to the substrate surface

• mode_spec (Attribute: mode_spec) –

  Type	ModeSpec
  Default	= ModeSpec(num_modes2, target_neffNone, num_pml(0,, 0), filter_polNone, angle_theta0.0, angle_phi0.0, precision’single’, bend_radiusNone, bend_axisNone, track_freq’central’, group_index_stepFalse, type’ModeSpec’)
  Description	ModeSpec defining waveguide mode properties.

• grid_resolution (Attribute: grid_resolution) –

  Type	int
  Default	= 15
  Description	Solver grid resolution per wavelength.

• max_grid_scaling (Attribute: max_grid_scaling) –

  Type	float
  Default	= 1.2
  Description	Maximal size increase between adjacent grid boundaries.

Supports: - Strip and rib geometries - Angled sidewalls - Modes in waveguide bends - Surface and sidewall loss models - Coupled waveguides

Attributes

grid_spec	Waveguide grid specification with overriding geometry.
height	Domain height (size in the normal direction).
lateral_axis	Lateral direction axis.
mode_area	Calculate the effective mode area.
mode_solver	Create a mode solver based on this waveguide structure
n_complex	Calculate the complex effective index.
n_eff	Calculate the effective index.
n_group	Calculate the group index.
structures	Waveguide structures for simulation, including the core(s), slabs (if any), and bottom cladding, if different from the top.
width	Domain width (size in the lateral direction).

Methods

plot([x, y, z, ax, source_alpha, monitor_alpha])	Plot each of simulation's components on a plane defined by one nonzero x,y,z coordinate.
plot_eps([x, y, z, freq, alpha, ...])	Plot each of simulation's components on a plane defined by one nonzero x,y,z coordinate.
plot_field(field_name[, val, eps_alpha, ...])	Plot the field for a ModeSolverData with Simulation plot overlaid.
plot_grid([x, y, z, ax])	Plot the cell boundaries as lines on a plane defined by one nonzero x,y,z coordinate.
plot_structures([x, y, z, ax])	Plot each of simulation's structures on a plane defined by one nonzero x,y,z coordinate.
plot_structures_eps([x, y, z, freq, alpha, ...])	Plot each of simulation's structures on a plane defined by one nonzero x,y,z coordinate.

wavelength

core_width

core_thickness

core_medium

clad_medium

box_medium

slab_thickness

clad_thickness

box_thickness

side_margin

sidewall_angle

gap

sidewall_thickness

sidewall_medium

surface_thickness

surface_medium

origin

length

propagation_axis

normal_axis

mode_spec

grid_resolution

max_grid_scaling

property lateral_axis

Lateral direction axis.

property height

Domain height (size in the normal direction).

property width

Domain width (size in the lateral direction).

property grid_spec

Waveguide grid specification with overriding geometry.

property structures

Waveguide structures for simulation, including the core(s), slabs (if any), and bottom cladding, if different from the top. For bend modes, the structure is a 270 degree bend regardless of length.

property mode_solver

Create a mode solver based on this waveguide structure

Return type:

ModeSolver

Example

>>> wg = waveguide.RectangularDielectric(
...     wavelength=1.55,
...     core_width=0.5,
...     core_thickness=0.22,
...     core_medium=Medium(permittivity=3.48**2),
...     clad_medium=Medium(permittivity=1.45**2),
...     num_modes=2,
... )
>>> mode_data = wg.mode_solver.solve()
>>> mode_data.n_eff.values
array([[2.4536054 1.7850305]], dtype=float32)

property n_eff

Calculate the effective index.

property n_complex

Calculate the complex effective index.

property n_group

Calculate the group index.

property mode_area

Calculate the effective mode area.

plot(x=None, y=None, z=None, ax=None, source_alpha=None, monitor_alpha=None, **patch_kwargs)

Plot each of simulation’s components on a plane defined by one nonzero x,y,z coordinate.

Parameters:

• x (float = None) – position of plane in x direction, only one of x, y, z must be specified to define plane.

• y (float = None) – position of plane in y direction, only one of x, y, z must be specified to define plane.

• z (float = None) – position of plane in z direction, only one of x, y, z must be specified to define plane.

• source_alpha (float = None) – Opacity of the sources. If None, uses Tidy3d default.

• monitor_alpha (float = None) – Opacity of the monitors. If None, uses Tidy3d default.

• ax (matplotlib.axes._subplots.Axes = None) – Matplotlib axes to plot on, if not specified, one is created.

Returns:

The supplied or created matplotlib axes.

Return type:

matplotlib.axes._subplots.Axes

plot_eps(x=None, y=None, z=None, freq=None, alpha=None, source_alpha=None, monitor_alpha=None, ax=None)

Plot each of simulation’s components on a plane defined by one nonzero x,y,z coordinate. The permittivity is plotted in grayscale based on its value at the specified frequency.

Parameters:

• x (float = None) – position of plane in x direction, only one of x, y, z must be specified to define plane.

• y (float = None) – position of plane in y direction, only one of x, y, z must be specified to define plane.

• z (float = None) – position of plane in z direction, only one of x, y, z must be specified to define plane.

• freq (float = None) – Frequency to evaluate the relative permittivity of all mediums. If not specified, evaluates at infinite frequency.

• alpha (float = None) – Opacity of the structures being plotted. Defaults to the structure default alpha.

• source_alpha (float = None) – Opacity of the sources. If None, uses Tidy3d default.

• monitor_alpha (float = None) – Opacity of the monitors. If None, uses Tidy3d default.

• ax (matplotlib.axes._subplots.Axes = None) – Matplotlib axes to plot on, if not specified, one is created.

Returns:

The supplied or created matplotlib axes.

Return type:

matplotlib.axes._subplots.Axes

plot_structures(x=None, y=None, z=None, ax=None)

Plot each of simulation’s structures on a plane defined by one nonzero x,y,z coordinate.

Parameters:

• x (float = None) – position of plane in x direction, only one of x, y, z must be specified to define plane.

• y (float = None) – position of plane in y direction, only one of x, y, z must be specified to define plane.

• z (float = None) – position of plane in z direction, only one of x, y, z must be specified to define plane.

• ax (matplotlib.axes._subplots.Axes = None) – Matplotlib axes to plot on, if not specified, one is created.

Returns:

The supplied or created matplotlib axes.

Return type:

matplotlib.axes._subplots.Axes

plot_structures_eps(x=None, y=None, z=None, freq=None, alpha=None, cbar=True, reverse=False, ax=None)

Plot each of simulation’s structures on a plane defined by one nonzero x,y,z coordinate. The permittivity is plotted in grayscale based on its value at the specified frequency.

Parameters:

• x (float = None) – position of plane in x direction, only one of x, y, z must be specified to define plane.

• y (float = None) – position of plane in y direction, only one of x, y, z must be specified to define plane.

• z (float = None) – position of plane in z direction, only one of x, y, z must be specified to define plane.

• freq (float = None) – Frequency to evaluate the relative permittivity of all mediums. If not specified, evaluates at infinite frequency.

• reverse (bool = False) – If False, the highest permittivity is plotted in black. If True, it is plotteed in white (suitable for black backgrounds).

• cbar (bool = True) – Whether to plot a colorbar for the relative permittivity.

• alpha (float = None) – Opacity of the structures being plotted. Defaults to the structure default alpha.

• ax (matplotlib.axes._subplots.Axes = None) – Matplotlib axes to plot on, if not specified, one is created.

Returns:

The supplied or created matplotlib axes.

Return type:

matplotlib.axes._subplots.Axes

plot_grid(x=None, y=None, z=None, ax=None, **kwargs)

Plot the cell boundaries as lines on a plane defined by one nonzero x,y,z coordinate.

Parameters:

• x (float = None) – position of plane in x direction, only one of x, y, z must be specified to define plane.

• y (float = None) – position of plane in y direction, only one of x, y, z must be specified to define plane.

• z (float = None) – position of plane in z direction, only one of x, y, z must be specified to define plane.

• ax (matplotlib.axes._subplots.Axes = None) – Matplotlib axes to plot on, if not specified, one is created.

• **kwargs – Optional keyword arguments passed to the matplotlib LineCollection. For details on accepted values, refer to Matplotlib’s documentation.

Returns:

The supplied or created matplotlib axes.

Return type:

matplotlib.axes._subplots.Axes

plot_field(field_name, val='real', eps_alpha=0.2, robust=True, vmin=None, vmax=None, ax=None, **sel_kwargs)

Plot the field for a ModeSolverData with Simulation plot overlaid.

Parameters:

• field_name (str) – Name of field component to plot (eg. ‘Ex’). Also accepts ‘E’ and ‘H’ to plot the vector magnitudes of the electric and magnetic fields, and ‘S’ for the Poynting vector.

• val (Literal['real', 'imag', 'abs', 'abs^2', 'dB'] = 'real') – Which part of the field to plot.

• eps_alpha (float = 0.2) – Opacity of the structure permittivity. Must be between 0 and 1 (inclusive).

• robust (bool = True) – If True and vmin or vmax are absent, uses the 2nd and 98th percentiles of the data to compute the color limits. This helps in visualizing the field patterns especially in the presence of a source.

• vmin (float = None) – The lower bound of data range that the colormap covers. If None, they are inferred from the data and other keyword arguments.

• vmax (float = None) – The upper bound of data range that the colormap covers. If None, they are inferred from the data and other keyword arguments.

• ax (matplotlib.axes._subplots.Axes = None) – matplotlib axes to plot on, if not specified, one is created.

• sel_kwargs (keyword arguments used to perform .sel() selection in the monitor data.) – These kwargs can select over the spatial dimensions (x, y, z), frequency or time dimensions (f, t) or mode_index, if applicable. For the plotting to work appropriately, the resulting data after selection must contain only two coordinates with len > 1. Furthermore, these should be spatial coordinates (x, y, or z).

Returns:

The supplied or created matplotlib axes.

Return type:

matplotlib.axes._subplots.Axes

__hash__()

Hash method.