class GaussianBeam[source]#

Bases: AngledFieldSource, PlanarSource, BroadbandSource

Gaussian distribution on finite extent plane.

  • attrs (dict = {}) – Dictionary storing arbitrary metadata for a Tidy3D object. This dictionary can be freely used by the user for storing data without affecting the operation of Tidy3D as it is not used internally. Note that, unlike regular Tidy3D fields, attrs are mutable. For example, the following is allowed for setting an attr obj.attrs['foo'] = bar. Also note that Tidy3D` will raise a TypeError if attrs contain objects that can not be serialized. One can check if attrs are serializable by calling obj.json().

  • name (Optional[str] = None) – Optional name for the source.

  • center (Union[tuple[Union[float, autograd.tracer.Box], Union[float, autograd.tracer.Box], Union[float, autograd.tracer.Box]], Box] = (0.0, 0.0, 0.0)) – [units = um]. Center of object in x, y, and z.

  • size (Union[tuple[Union[pydantic.v1.types.NonNegativeFloat, autograd.tracer.Box], Union[pydantic.v1.types.NonNegativeFloat, autograd.tracer.Box], Union[pydantic.v1.types.NonNegativeFloat, autograd.tracer.Box]], Box]) – [units = um]. Size in x, y, and z directions.

  • source_time (Union[GaussianPulse, ContinuousWave, CustomSourceTime]) – Specification of the source time-dependence.

  • num_freqs (ConstrainedIntValue = 1) – Number of points used to approximate the frequency dependence of injected field. A Chebyshev interpolation is used, thus, only a small number of points, i.e., less than 20, is typically sufficient to obtain converged results.

  • direction (Literal['+', '-']) – Specifies propagation in the positive or negative direction of the injection axis.

  • angle_theta (float = 0.0) – [units = rad]. Polar angle of the propagation axis from the injection axis.

  • angle_phi (float = 0.0) – [units = rad]. Azimuth angle of the propagation axis in the plane orthogonal to the injection axis.

  • pol_angle (float = 0) – [units = rad]. Specifies the angle between the electric field polarization of the source and the plane defined by the injection axis and the propagation axis (rad). pol_angle=0 (default) specifies P polarization, while pol_angle=np.pi/2 specifies S polarization. At normal incidence when S and P are undefined, pol_angle=0 defines: - Ey polarization for propagation along x.- Ex polarization for propagation along y.- Ex polarization for propagation along z.

  • waist_radius (PositiveFloat = 1.0) – [units = um]. Radius of the beam at the waist.

  • waist_distance (float = 0.0) – [units = um]. Distance from the beam waist along the propagation direction. When direction is + and waist_distance is positive, the waist is on the - side (behind) the source plane. When direction is + and waist_distance``is negative, the waist is on the ``+ side (in front) of the source plane.


>>> pulse = GaussianPulse(freq0=200e12, fwidth=20e12)
>>> gauss = GaussianBeam(
...     size=(0,3,3),
...     source_time=pulse,
...     pol_angle=np.pi / 2,
...     direction='+',
...     waist_radius=1.0)

See also




Inherited Common Usage


Hash method.