List of material parameters

A list of material parameters that the user can define is provided below, in bold, along with a brief description.

Dielectric material

In FDTD++, a dielectric material is defined in the materials file in the main materials block:

material n
{
    epsr #
}

where # is the relative permittivity.

Conductor

In FDTD++, a conductor is defined in the materials file by providing $\sigma$ in a conductor block:

conductor
{
    sigma #
}

where # is the value of $\sigma$. Note that conductor, {, and } should each be on their own lines.

Perfect electric conductor

In FDTD++, a PEC is defined in the materials file by declaring a PEC block:

PEC
{
}

Note that PEC, {, and } should each be on their own lines. Note also that a PEC block should not be defined in combination with any other models, otherwise the simulation will stop and report an error.

Drude model

In FDTD++, a Drude model is defined in the materials file by providing $\omega_p$ and $\gamma$ in a Drude block:

Drude
{
    omegap #1
    gamma #2
}

where #1 and #2 are the values of $\omega_p$ and $\gamma$ (both in eV), respectively. Note that Drude, {, and } should each be on their own lines.

Hydrodynamic Drude model

The hydrodynamic Drude model is currently only implemented in the research version of FDTD++, but will be available in future releases of FDTD++. In the meantime, see the work by J. M. McMahon et al.

Lorentz oscillator model

In FDTD++, a Lorentz oscillator model is defined in the materials file by providing $\Delta \varepsilon_p$, $\omega_p$, and $\delta$ In a Lorentz block:

Lorentz
{
    depsr #1
    omegap #2
    delta #3
}

where #1, #2, and #3 are the values of $\Delta \varepsilon_p$ (unitless), $\omega_p$ (in eV), and $\delta$ (in eV), respectively. Note that Lorentz, {, and } should each be on their own lines.

Debye model

In FDTD++, a Debye model is defined in the materials file by providing $\omega_p$ and $\gamma$ in a Debye block:

Debye
{
    depsr #1
    tau #2
}

where #1 and #2 are the values of $\Delta \varepsilon$ (unitless) and $\tau$ (both in s$^{-1}$), respectively. Note that Debye, {, and } should each be on their own lines.