arXiv 0811.05512008-11physics.optics

Improved focusing with Hypergeometric-Gaussian type-II optical modes

Ebrahim Karimi, Bruno Piccirillo, Lorenzo Marrucci, Enrico Santamato

备注：: 6 pages, 3 figures
发表信息：: Opt. Exp., 16, 21069 (2008)
DOI：: 10.1364/OE.16.021069

英文摘要：

We present a novel family of paraxial optical beams having a confluent hypergeometric transverse profile, which we name hypergeometric Gauss modes of type-II (HyGG-II). These modes are eigenmodes of the photon orbital angular momentum and they have the lowest beam divergence at waist of HyGG-II among all known finite power families of paraxial modes. We propose to exploit this feature of HyGG-II modes for generating, after suitable focusing, a "light needle" having record properties in terms of size and aspect ratio, possibly useful for near-field optics applications.

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