RF Materials Models

RF Materials Models#

`tidy3d.PECMedium`	Perfect electrical conductor class.
`tidy3d.PMCMedium`	Perfect magnetic conductor class.
`tidy3d.rf.LossyMetalMedium`	Lossy metal that can be modeled with a surface impedance boundary condition (SIBC).
`tidy3d.rf.SurfaceImpedanceFitterParam`	Advanced parameters for fitting surface impedance of a `LossyMetalMedium`.
`tidy3d.rf.HammerstadSurfaceRoughness`	Modified Hammerstad surface roughness model.
`tidy3d.rf.HuraySurfaceRoughness`	Huray surface roughness model.

The PECMedium and LossyMetalMedium classes can be used to model metallic materials.

# lossless metal
my_pec = PECMedium()

# lossy metal (conductivity in S/um)
my_lossy_metal = LossyMetalMedium(conductivity=58, freq_range=(1e9, 10e9))

Note that the unit of conductivity is S/um and the unit of freq_range is Hz. The LossyMetalMedium class implements the surface impedance boundary condition (SIBC). It can accept surface roughness specifications using the Hammerstad or Huray models. Please refer to their respective documentation pages for details. Edge singularity correction is also available but turned off by default at this time.

Note

When modeling lossy metals, always be sure to check the skin depth — if the skin depth is significant compared to the geometry size, then LossyMetalMedium may be not accurate. In that case, use a regular dispersive medium instead.

`tidy3d.Medium`	Dispersionless medium.
`tidy3d.plugins.dispersion.FastDispersionFitter`	Tool for fitting refractive index data to get a dispersive medium described by `PoleResidue` model.

To model lossless dielectrics, use the regular Medium.

# lossless dielectric
my_lossless_dielectric = Medium(permittivity=2.2)

To model a lossy dielectric with constant loss tangent, use the constant_loss_tangent_model() method of the tidy3d.plugins.dispersion.FastDispersionFitter utility class.

# lossy dielectric (constant loss tangent)
my_lossy_dielectric = FastDispersionFitter.constant_loss_tangent_model(
    eps_real=4.4,
    loss_tangent=0.002,
    frequency_range=(1e9, 5e9)
)

More advanced material models, including frequency dependence and anisotropy, are also available in Tidy3D.