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arXiv · 1005.1470

Efficient Beam Converter for the Generation of Femtosecond Vortices

Vladlen G. Shvedov·Cyril Hnatovsky·Wieslaw Krolikowski·Andrei V. Rode
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Abstract

We describe an optical beam converter for an efficient transformation of Gaussian femtosecond laser beams to single- or double-charge vortex beams showing no spatial or topological charge dispersion. The device achieves a conversion efficiency of 75% for single- and 50% for double-charge vortex beams and can operate with high energy broad bandwidth pulses. We also show that the topological charge of a femtosecond vortex beam can be determined by analyzing its intensity distribution in the focal area of a cylindrical lens.

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Vladlen G. Shvedov, Cyril Hnatovsky, Wieslaw Krolikowski, Andrei V. Rode. 2010-05-10. Efficient Beam Converter for the Generation of Femtosecond Vortices. https://doi.org/10.1364/ol.35.002660

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