coefficients

deeptrack.backend.mie.coefficients(m: float | complex, a: float, L: int) → tuple[ndarray, ndarray]

Calculate the Mie scattering coefficients for a spherical particle.

These coefficients are used in the computation of the scattering and absorption of light by the particle. The terms up to (and including) order L are calculated using Riccati-Bessel polynomials.

Parameters

m: float | complex

The relative refractive index of the particle n_particle / n_medium.

a: float

The radius of the particle (> 0).

L: int

The maximum order of the spherical harmonics to be calculated. If 0, two empty arrays are returned.

Returns

tuple[np.ndarray, np.ndarray]

A tuple containing two arrays of complex numbers, A and B, which are the Mie scattering coefficients up to (and including) order L.