Abstract:
The structure of the interference field resulted from the combination of the wave fields of subbeams with apertures located on sides of a regular hexagon is studied. The field on each subapertures is a truncated Gaussian beam with the constant phase shift between neighbor subapertures so as the total phase incursion becomes equal to 2π when walking around the hexagon. It is ascertained that the total angular momentum of the beam synthesized in such a way is zero. There is a region in the central part of the beam where the integral of the density of orbital angular momentum gives the unit orbital angular momentum, and the circulation of the phase gradient at the boundary of this region gives unit topological charge.
Keywords:
vortex beam, coherent beam array, orbital angular momentum, topological charge
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