The Transition Boundary Condition is used on interior boundaries to model a sheet of a medium that should be geometrically thin but does not have to be electrically thin. It represents a discontinuity in the tangential electric field. Mathematically it is described by a relation between the electric field discontinuity and the induced surface current density:
This section is only available for the Electromagnetic Waves, Beam Envelopes interface. Select a Propagation direction —
Normal direction (the default) or
From wave vector. The
Normal direction option assumes that the waves in the layer propagate essentially in the normal direction, whereas the
From wave vector option assumes that the tangential wave vector component is continuous at the layer boundaries, as specified by the wave vectors
k1 and
k2 for the Electromagnetic Waves, Beam Envelopes interface. The normal component for the wave vector in the layer is obtained from the wave number, given the specified material parameters. Thus, this option implements Snell’s law of refraction for the layer, which makes this option useful also for dielectric layers.
Select an Electric displacement field model —
Relative permittivity,
Refractive index (the default),
Loss tangent, loss angle,
Loss tangent, dissipation factor,
Dielectric loss,
Drude-Lorentz dispersion model,
Debye dispersion model, or
Sellmeier dispersion model. See the
Wave Equation, Electric node,
Electric Displacement Field section, for all settings.
Select the Electrically thick layer check box (unselected by default) to make the two domains adjacent to the boundary uncoupled. When the
Electrically thick layer check box is unselected, enter a
Thickness d (SI unit: m). The default is 0.01 m.