We produce coherence vortices experimentally and numerically due to the orbital angular momentum of light beams and study the dependence of their bright ring area and dark region on their different orders. This is a linear dependence with a slope proportional to the bright ring area or dark area. We show that it is possible to estimate any order of coherence vortices, including fractional orders, just by calculating the bright ring area or dark area of the vortices for some specific parameters of the incident beam.

It is well known that coherent Bessel beam, a nondiffracting class of beam, possesses the ability of self-reconstructing or self-healing in the presence of obstacles. Here, we generated partially coherent Bessel and Gaussian beams using a spatial light modulator and studied the speckle pattern intensity in propagation after some speckles were blocked. We demonstrated that these partially coherent beams are unexpectedly robust against scattering by objects, overcoming the coherent Bessel beam and remaining independent of any special class of partially coherent beams.

Determination of orbital angular momentum of optical vortex beams has attracted the attention of many researchers over the last few years. For some applications, it is convenient to use a partially coherent vortex beam because of its robustness. In this work, we developed a method to measure the topological charge of a partially coherent vortex beam. Our method relies simply in the measurement of the minimum radius of a zero contour of the modulus of the cross-correlation function and in the measurement of the full width at half maximum of its central spot.

coherent optical vortices have promising applications in quantum and classical optical communication. they add new degrees of freedom to code information. in this context, to implement a tool enabling sorting of spatially multiplexed vortex states is fundamental. By other hand, spatially incoherent vortices can be more robust in propagation through noise media, such as turbulent atmosphere or obstacles that block part of the light. therefore, in this work we propose directly applying a highresolution sorting scheme to spatially incoherent vortex states.

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