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Evolution of Singularities in a Vortex Beam
Evolution of Singularities in a Vortex Beam
Thomas van Dijk and Taco Visser
Vrije Universiteit and TU Delft
We study the evolution of phase singularities and coherence
singularities in a Laguerre-Gauss beam that is rendered partially
coherent by letting it pass through a spatial light modulator.
The original beam has an on-axis minumum of intensity–a phase
singularity–that transforms into a maximum of the far-field intensity.
In contrast, although the original beam has no coherence
singularities, such singularities are found to develop as the beam
propagates. This disappearance of one kind of singularity and
the gradual appearance of another is illustrated with numerical
examples.
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