Figure 1: Conversion from orthogonal azimuthal amplitude distributions to a topological charge.
From: Photons, phonons, and plasmons with orbital angular momentum in plasmas
(a) and (d) are the amplitude and phase distributions of the mode Aβ|cos(lϕ). (b) and (e) are those of the mode Aβ|sin(lϕ). (c) and (f) are those of the modes with OAM. The azimuthal mode number l is 2. The amplitudes are normalized by their maximum values and the coordinates are normalized by μr. The phases are measured by rad. It shows that a photon with OAM can be constructed from modes without OAM via the coherent interference.
