Self-focusing vortex beams
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Femtosecond Laser Filaments for Use in Sub-Diffraction-Limited Imaging and Remote Sensing
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Optics Letters
|May 14, 2021
Abstract:
A class of wide-stationary optical sources with a specially designed degree of coherence profile is introduced for radiating spectral densities with a vortex whose core's location and size can be controlled at a specified range. This is achieved by modeling of the source coherence state as a combination of a helicoidal separable phase and a Cartesian phase factor, depending on the separation between the $ n $th power of the radius-vectors of two points.
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