Struct SphericalChannel 

struct SphericalChannel<const N: usize> {
    vector: [Jet<N>; 3],
    k: Jet<N>,
    kz: Jet<N>,
    sine: Jet<N>,
    cosine: Jet<N>,
    azimuth: Jet<N>,
    area: Jet<N>,
}

One diffraction channel of a 2D array of spheres in one direction: the plane wave (qx, qy, ±kz) and the angles at which the multipole coefficients are evaluated, as jets in the slots above.

Fields

vector: [Jet<N>; 3]

The plane wavevector (qx, qy, ±kz): +kz on side 0, -kz on side 1.

k: Jet<N>

Wavenumber of the medium on the chosen root, see SphericalChannel::new.

kz: Jet<N>

Normal wavenumber sqrt(k^2 - q^2) with a positive imaginary part or a nonnegative real value.

sine: Jet<N>

sin(theta) with a nonnegative real part.

cosine: Jet<N>

cos(theta) = ±kz / k.

azimuth: Jet<N>

exp(i phi) = (qx + i qy) / |q|, or 1 at normal incidence.

area: Jet<N>

Unit-cell area.

Implementations

impl<const N: usize> SphericalChannel<N>

fn new( k: Complex, q: [f64; 2], side: usize, area: f64, fixed_q: bool, ) -> Result<Self>

The channel of transverse wavevector q on side (0 up, 1 down).

k is the principal root of k^2, as upstream sw.periodic_to_pw computes k = sqrt(kx^2 + ky^2 + kz^2), so a wavenumber with a negative real part gives the same channel as its negative. kz = sqrt(k^2 - q^2) takes the root with a positive imaginary part, or the nonnegative real root, as upstream kz_s: the wave decays or propagates in its direction of travel. Upstream replaces kz = 0 by 1e-20 (1 + i); this returns an error when the computed kz is exactly zero.

fn entry( &self, mode: Mode, pol: u8, position: [f64; 3], helicity: bool, ) -> [Jet<N>; 2]

The incident and radiated coefficients of mode at position for the plane polarization pol: [pw.to_sw, sw.periodic_to_pw] with the position phase.