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arXiv · 0905.0562

Efficient generation and sorting of orbital angular momentum eigenmodes of light by thermally tuned q-plates

Ebrahim Karimi·Bruno Piccirillo·Eleonora Nagali·Lorenzo Marrucci·Enrico Santamato
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Abstract

We present methods for generating and for sorting specific orbital angular momentum (OAM) eigenmodes of a light beam with high efficiency, using a liquid crystal birefringent plate with unit topological charge, known as \qo{q-plate}. The generation efficiency has been optimized by tuning the optical retardation of the q-plate with temperature. The measured OAM $m=\pm2$ eigenmodes generation efficiency from an input TEM$_{00}$ beam was of 97%. Mode sorting of the two input OAM $m=\pm2$ eigenmodes was achieved with an efficiency of 81% and an extinction-ratio (or cross-talk) larger than 4.5:1.

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Ebrahim Karimi, Bruno Piccirillo, Eleonora Nagali, Lorenzo Marrucci, Enrico Santamato. 2009-05-05. Efficient generation and sorting of orbital angular momentum eigenmodes of light by thermally tuned q-plates. https://doi.org/10.1063/1.3154549

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