Correlation-induced orbital angular momentum changes

  title={Correlation-induced orbital angular momentum changes},
  author={Yongtao Zhang and Olga Korotkova and Yangjian Cai and Greg Gbur},
  journal={arXiv: Optics},
We demonstrate that the orbital angular momentum flux density of a paraxial light beam can change on propagation in free space. These changes are entirely due to the spatial coherence state of the source, and the effect is analogous to correlation-induced changes in the intensity, spectrum and polarization of a beam. The use of the source coherence state to control the width, shape, and transverse shifts of the OAM flux density is demonstrated with numerical examples. 

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