Sources and detectors

Sources and detectors#

A source specifies both a spatial field pattern and a temporal signal. A detector reduces the evolving state to data useful after—or during—the run.

Temporal profiles#

WaveCharacter accepts exactly one of free-space wavelength, frequency, or period. Source classes can use continuous-wave, Gaussian-windowed, or custom time profiles. Broadband pulses cover multiple frequencies in one run, but every requested phasor still needs sufficient cycles and a clean accumulation window.

Validated temporal behavior includes continuous and Gaussian profiles, custom profiles, pulsed-versus-CW transmission, and dispersive-source correction.

Spatial excitation#

  • PointDipoleSource injects a localized electric current.

  • UniformPlaneSource injects a linearly polarized plane field over a finite plane.

  • GaussianPlaneSource adds a transverse Gaussian amplitude and phase profile.

  • ModePlaneSource injects a computed cross-sectional eigenmode.

  • TFSF sources bound a total-field region and cancel the incident field outside it.

Total-field scattered-field source enclosing a scatterer

TFSF injection is especially useful when scattered power must be measured without subtracting a large incident field numerically.#

Detector choices#

Detector

Produces

Use it for

FieldDetector

sampled \(E\)/\(H\) in space and time

animations, transients, custom reductions

PhasorDetector

complex frequency-domain fields

phase, impedance, standing waves

PoyntingFluxDetector

integrated instantaneous power flow

pulse energy and time-domain diagnostics

PhasorPoyntingFluxDetector

frequency-resolved complex power

spectra and \(R/T\)

ModeOverlapDetector

complex modal amplitudes

port transmission, reflection, and S-parameters

EnergyDetector

electromagnetic energy

decay and stability checks

Sign and normalization#

For phasors, the time-average Poynting vector is

\[ \langle\mathbf S\rangle=\frac12\operatorname{Re}\left(\mathbf E\times\mathbf H^*\right). \]

Detector face orientation determines the sign. For scattering parameters, normalize output mode power by an incident-mode calibration produced with the same source, grid, accumulation convention, and reference plane. The benchmark suite checks phasor/time-domain consistency and passive-power bounds precisely because normalization bugs can otherwise look like excellent device performance.