How do I create an anisotropic material?

Date	Category
2023-12-05 19:12:04	Mediums

To create fully anisotropic mediums including all 9 components of the permittivity and conductivity tensors, you can use the tidy3d.FullyAnisotropicMedium object. The provided permittivity tensor and the symmetric part of the conductivity tensor must have coinciding main directions. However, a non-symmetric conductivity tensor can be used to model magneto-optic effects. Note that dispersive properties and subpixel averaging are currently not supported for fully anisotropic materials.

perm = [[2, 0, 0], [0, 1, 0], [0, 0, 3]]
cond = [[0.1, 0, 0], [0, 0, 0], [0, 0, 0]]
anisotropic_dielectric = FullyAnisotropicMedium(permittivity=perm, conductivity=cond)

Alternatively, you can create a diagonally anisotropic material, using the tidy3d.AnisotropicMedium(xx=medium_xx, yy=medium_yy, zz=medium_zz) object, and then include three medium objects defining the diagonal elements of the permittivity tensor. In this case, the medium objects can be of type Medium, PoleResidue, Sellmeier, Lorentz, Debye, or Drude. For example:

medium_xx = Medium(permittivity=4.0)
medium_yy = Medium(permittivity=4.1)
medium_zz = Medium(permittivity=3.9)
anisotropic_dielectric = AnisotropicMedium(xx=medium_xx, yy=medium_yy, zz=medium_zz)