tidy3d.CustomLorentz#

class CustomLorentz[source]#

Bases: CustomDispersiveMedium, Lorentz

A spatially varying dispersive medium described by the Lorentz model.

Parameters:
  • name (Attribute: name) –

    Type

    Optional[str]

    Default

    = None

    Description

    Optional unique name for medium.

  • frequency_range (Attribute: frequency_range) –

    Type

    Optional[Tuple[float, float]]

    Default

    = None

    Units

    (Hz, Hz)

    Description

    Optional range of validity for the medium.

  • allow_gain (Attribute: allow_gain) –

    Type

    bool

    Default

    = False

    Description

    Allow the medium to be active. Caution: simulations with a gain medium are unstable, and are likely to diverge.Simulations where ‘allow_gain’ is set to ‘True’ will still be charged even if diverged. Monitor data up to the divergence point will still be returned and can be useful in some cases.

  • nonlinear_spec (Attribute: nonlinear_spec) –

    Type

    Union[NonlinearSpec, NonlinearSusceptibility]

    Default

    = None

    Description

    Nonlinear spec applied on top of the base medium properties.

  • modulation_spec (Attribute: modulation_spec) –

    Type

    Optional[ModulationSpec]

    Default

    = None

    Description

    Modulation spec applied on top of the base medium properties.

  • heat_spec (Attribute: heat_spec) –

    Type

    Union[FluidSpec, SolidSpec, NoneType]

    Default

    = None

    Description

    Specification of the medium heat properties. They are used for solving the heat equation via the HeatSimulation interface. Such simulations can be used for investigating the influence of heat propagation on the properties of optical systems. Once the temperature distribution in the system is found using HeatSimulation object, Simulation.perturbed_mediums_copy() can be used to convert mediums with perturbation models defined into spatially dependent custom mediums. Otherwise, the heat_spec does not directly affect the running of an optical Simulation.

  • eps_inf (Attribute: eps_inf) –

    Type

    SpatialDataArray

    Default

    Units

    None (relative permittivity)

    Description

    Relative permittivity at infinite frequency (\(\epsilon_\infty\)).

  • coeffs (Attribute: coeffs) –

    Type

    Tuple[Tuple[tidy3d.components.data.data_array.SpatialDataArray, tidy3d.components.data.data_array.SpatialDataArray, tidy3d.components.data.data_array.SpatialDataArray], …]

    Default

    Units

    (None (relative permittivity), Hz, Hz)

    Description

    List of (\(\Delta\epsilon_i, f_i, \delta_i\)) values for model.

  • interp_method (Attribute: interp_method) –

    Type

    Literal[‘nearest’, ‘linear’]

    Default

    = nearest

    Description

    Interpolation method to obtain permittivity values that are not supplied at the Yee grids; For grids outside the range of the supplied data, extrapolation will be applied. When the extrapolated value is smaller (greater) than the minimal (maximal) of the supplied data, the extrapolated value will take the minimal (maximal) of the supplied data.

  • subpixel (Attribute: subpixel) –

    Type

    bool

    Default

    = False

    Description

    If True and simulation’s subpixel is also True, applies subpixel averaging of the permittivity on the interface of the structure, including exterior boundary and intersection interfaces with other structures.

Notes

The frequency-dependence of the complex-valued permittivity is described by:

\[\epsilon(f) = \epsilon_\infty + \sum_i \frac{\Delta\epsilon_i f_i^2}{f_i^2 - 2jf\delta_i - f^2}\]

Example

>>> x = np.linspace(-1, 1, 5)
>>> y = np.linspace(-1, 1, 6)
>>> z = np.linspace(-1, 1, 7)
>>> coords = dict(x=x, y=y, z=z)
>>> eps_inf = SpatialDataArray(np.ones((5, 6, 7)), coords=coords)
>>> d_epsilon = SpatialDataArray(np.random.random((5, 6, 7)), coords=coords)
>>> f = SpatialDataArray(1+np.random.random((5, 6, 7)), coords=coords)
>>> delta = SpatialDataArray(np.random.random((5, 6, 7)), coords=coords)
>>> lorentz_medium = CustomLorentz(eps_inf=eps_inf, coeffs=[(d_epsilon,f,delta),])
>>> eps = lorentz_medium.eps_model(200e12)

See also

CustomPoleResidue:

A spatially varying dispersive medium described by the pole-residue pair model.

Notebooks
Lectures

Attributes

Methods

eps_dataarray_freq(frequency)

Permittivity array at frequency.

eps_inf#
coeffs#
eps_dataarray_freq(frequency)[source]#

Permittivity array at frequency.

Parameters:

frequency (float) – Frequency to evaluate permittivity at (Hz).

Returns:

The permittivity evaluated at frequency.

Return type:

Tuple[SpatialDataArray, SpatialDataArray, SpatialDataArray]

__hash__()#

Hash method.