tidy3d.FluxTimeMonitor

class FluxTimeMonitor

Bases: AbstractFluxMonitor, TimeMonitor

Monitor that records power flux in the time domain.

Parameters:

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

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

• name (str) – Unique name for monitor.

• interval_space (tuple[Literal[1], Literal[1], Literal[1]] = (1, 1, 1)) – Number of grid step intervals between monitor recordings. If equal to 1, there will be no downsampling. If greater than 1, the step will be applied, but the first and last point of the monitor grid are always included. Not all monitors support values different from 1.

• colocate (bool = True) – Governed by use_colocated_integration and not set independently for surface-integration monitors: it mirrors that value, so the solver records colocated fields exactly when the integration is colocated.

• use_colocated_integration (bool = True) – Selects the surface-integration scheme. If True (default), the integral is computed from fields colocated to the grid cell boundaries (primal nodes). If False, it is computed directly on the native Yee-staggered grid: the tangential field components stay at their tangential positions.

• start (NonNegativeFloat = 0.0) – [units = sec]. Time at which to start monitor recording.

• stop (Optional[NonNegativeFloat] = None) – [units = sec]. Time at which to stop monitor recording. If not specified, record until end of simulation.

• interval (Optional[PositiveInt] = None) – Sampling rate of the monitor: number of time steps between each measurement. Set interval to 1 for the highest possible resolution in time. Higher integer values downsample the data by measuring every interval time steps. This can be useful for reducing data storage as needed by the application.

• normal_dir (Optional[Literal['+', '-']] = None) – Direction of the surface monitor’s normal vector w.r.t. the positive x, y or z unit vectors. Must be one of '+' or '-'. Applies to surface monitors only, and defaults to '+' if not provided.

• exclude_surfaces (Optional[tuple[Literal['x-', 'x+', 'y-', 'y+', 'z-', 'z+'], ...]] = None) – Surfaces to exclude in the integration, if a volume monitor.

Notes

If the monitor geometry is a 2D box, the total flux through this plane is returned, with a positive sign corresponding to power flow in the positive direction along the axis normal to the plane. If the geometry is a 3D box, the total power coming out of the box is returned by integrating the flux over all box surfaces (except the ones defined in exclude_surfaces).

Example

>>> monitor = FluxTimeMonitor(
...     center=(1,2,3),
...     size=(2,2,0),
...     start=1e-13,
...     stop=5e-13,
...     interval=2,
...     name='flux_vs_time')

Attributes

use_colocated_integration
colocate
normal_dir
exclude_surfaces
start
stop
interval
interval_space
name
size
center

Methods

storage_size(num_cells, tmesh)

Size of monitor storage given the number of points after discretization.

storage_size(num_cells, tmesh)

Size of monitor storage given the number of points after discretization.