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arXiv · 1211.4163

Generation and dynamics of optical beams with polarization singularities

Filippo Cardano·Ebrahim Karimi·Lorenzo Marrucci·Corrado de Lisio·Enrico Santamato
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Abstract

We present a convenient method to generate vector beams of light having polarization singularities on their axis, via partial spin-to-orbital angular momentum conversion in a suitably patterned liquid crystal cell. The resulting polarization patterns exhibit a C-point on the beam axis and an L-line loop around it, and may have different geometrical structures such as \qo{lemon}, \qo{star}, and \qo{spiral}. Our generation method allows us to control the radius of L-line loop around the central C-point. Moreover, we investigate the free-air propagation of these fields across a Rayleigh range.

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Filippo Cardano, Ebrahim Karimi, Lorenzo Marrucci, Corrado de Lisio, Enrico Santamato. 2013-01-07. Generation and dynamics of optical beams with polarization singularities. https://doi.org/10.1364/oe.21.008815

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