pml

Functions related to perfectly matched layers.

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class fmmax.pml.PMLParams(num_x: int, num_y: int, a_max: float = 4.0, p: float = 4.0, sigma_max: float = 1.0)

Stores parameters that define perfectly matched layers.

num_x

The number of grid points occupied by the PML, in the x-direction.

Type:

int

num_y

The number of grid points occupied by the PML, in the y-direction.

Type:

int

a_max

The strength parameter for uniaxial PML.

Type:

float

p

The exponent parameter for uniaxial PML.

Type:

float

sigma_max

The conductivity parameter for uniaxial PML.

Type:

float

fmmax.pml.apply_uniaxial_pml(permittivity: Array, pml_params: PMLParams) → Tuple[Tuple[Array, Array, Array, Array, Array], Tuple[Array, Array, Array, Array, Array]]

Generate the permittivity and permeability tensor elements for uniaxial pml.

The PML assumes that the unit cell has primitive lattice vectors u and v which are parallel to x and y axes, respectively.

This function is appropriate for isotropic nonmagnetic media, but the permittivities and permeabilities generated are anisotropic.

Parameters:

• permittivity – isotropic permittivity

• pml_params – The parameters defining the perfectly matched layer dimensions and absorption characteristics.

Returns:

The permittivity and permeability tensor elements, `(

(eps_xx, eps_xy, eps_yx, eps_yy, eps_zz), (mu_xx, mu_xy, mu_yx, mu_yy, mu_zz),

)`.