Achromatic orbital angular momentum generator

  title={Achromatic orbital angular momentum generator},
  author={Fr{\'e}d{\'e}ric Bouchard and Harjaspreet Mand and Mohammad Mirhosseini and Ebrahim Karimi and Robert W. Boyd},
  journal={New Journal of Physics},
We describe a novel approach for generating light beams that carry orbital angular momentum (OAM) by means of total internal reflection in an isotropic medium. A continuous space-varying cylindrically symmetric reflector, in the form of two glued hollow axicons, is used to introduce a nonuniform rotation of polarization into a linearly polarized input beam. This device acts as a full spin-to-orbital angular momentum convertor. It functions by switching the helicity of the incoming beamʼs… 

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