magneticScattering.scatter.Beam#

class Beam(wavelength, fwhm, pol)#

Bases: object

Describes the properties of the beam.

Parameters:

wavelengthfloat: The wavelength of the beam in meters.
fwhmnp.ndarray | 2-tuple | 2-list: The full width at half maximum of the beam in the x and y directions.
pol4-list of float: The polarization of the beam in Stokes parameters.

Methods

calc_density_matrix

Converts the Stokes polarization vector to a density matrix

Attributes

`degree_of_pol`	The degree of polarisation.
`density_matrix`	Polarization density matrix.
`fwhm`	The full width at half maximum of the beam.
`pol`	The polarisation of the beam.
`sigma`	The spread of the beam.
`tracker`	Function to notify parent of any changes to the class.
`wavelength`	The wavelength of the beam.

calc_density_matrix()#

Converts the Stokes polarization vector to a density matrix

Returns:

np.ndarray: The density matrix of the beam.
np.ndarray: The degree of polarization.

Notes

The expression for converting the Strokes polarization “vector” to a density matrix is:

\[\rho = \frac{1}{2}(\vec{P} \cdot \vec{\sigma})\]

where \(\vec{P}\) is the Stokes polarization vector and \(\sigma\) is the vector containing the Pauli spin matrices and the identity matrix \((\sigma_0 = \mathbf{I})\).

property degree_of_pol#: The degree of polarisation.

property density_matrix#: Polarization density matrix.

property fwhm#: The full width at half maximum of the beam.

property pol#: The polarisation of the beam.

property sigma#: The spread of the beam.

property tracker#: Function to notify parent of any changes to the class.

property wavelength#: The wavelength of the beam.