The Wave Equation, Electric node is the main node for the Electromagnetic Waves, Transient interface. The governing equation can be written in the form

for transient problems with the constitutive relations B = μ0μrH and D = ε0εrE. Other constitutive relations can also be handled for transient problems.

Select an Electric displacement field model—Relative permittivity, Refractive index (the default), Polarization, Remanent electric displacement, or Drude-Lorentz dispersion model.

When Relative permittivity is selected, the default Relative permittivity εr (dimensionless) takes values From material. For User defined select Isotropic, Diagonal, Symmetric, or Anisotropic and enter values or expressions in the field or matrix.

When Refractive index is selected, the default Refractive index n (dimensionless) takes the value From material. To specify the refractive index and assume a relative permeability of unity and zero conductivity, for one or both of the options, select User defined then choose Isotropic, Diagonal, Symmetric, or Anisotropic. Enter values or expressions in the field or matrix.

For Polarization enter coordinates for the Polarization P (SI unit: C/m2).

For Remanent electric displacement enter coordinates for the Remanent electric displacement Dr (SI unit: C/m2). Then select User defined or From Material as above for the Relative permittivity εr.

For Drude-Lorentz Dispersion Model select User defined or From Material for the Relative permittivity, high-frequency ε∞ and enter a value for the Plasma frequency ωp (SI unit: rad/s).

When Drude-Lorentz Dispersion Model is selected, the Drude-Lorentz Polarization subnode is available from the context menu (right-click the parent node) or from the Physics toolbar, Attributes menu. Each Drude-Lorentz Polarization subnode adds another polarization term Pn to the electric displacement field D, defined by

For more information, see the Drude-Lorentz Polarization feature.

This section is available if Relative permittivity, Polarization, or Remanent electric displacement are chosen as the Electric displacement field model.

Select the Constitutive relation — Relative permeability (the default), Remanent flux density, or Magnetization.

For Relative permeability the relative permeability μr uses values From material. For User defined select Isotropic, Diagonal, Symmetric, or Anisotropic based on the characteristics of the magnetic field, and then enter values or expressions in the field or matrix.

For Remanent flux density the relative permeability μr uses values From material. For User defined select Isotropic, Diagonal, Symmetric, or Anisotropic based on the characteristics of the magnetic field, and then enter values or expressions in the field or matrix. Then enter coordinates for the Remanent flux density Br (SI unit: T).

For Magnetization enter coordinates for M (SI unit: A/m).

This section is available if Relative permittivity, Polarization, or Remanent electric displacement are chosen as the Electric displacement field model.

By default, the Electrical conductivity σ (SI unit: S/m) uses values From material.