Higher order optical vortices and formation of speckles.

@article{Reddy2013HigherOO,
  title={Higher order optical vortices and formation of speckles.},
  author={Salla Gangi Reddy and Shashi Prabhakar and Ashok Kumar and J. Banerji and R. P. Singh},
  journal={Optics letters},
  year={2013},
  volume={39 15},
  pages={
          4364-7
        }
}
We have experimentally generated higher order optical vortices and scattered them through a ground glass plate that results in speckle formation. Intensity autocorrelation measurements of speckles show that their size decreases with an increase in the order of the vortex. It implies an increase in the angular diameter of the vortices with their order. The characterization of vortices in terms of their annular bright ring also helps us to understand these observations. The results may find… 

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