title: Improved focusing with hypergeometric-gaussian type-II optical modes.
abstract: 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 in the waist of HyGG-II among all known finite power paraxial modes families. 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.
authors.affiliation: Dipartimento di Scienze Fisiche, Università degli Studi di Napoli Federico II, Complesso di Monte S. Angelo, 80126 via Cintia Napoli, Italy. karimi@na.infn.it
authors.forename: Ebrahim
authors.initials: E
authors.lastname: Karimi
authors.forename: Bruno
authors.initials: B
authors.lastname: Piccirillo
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Marrucci
authors.forename: Enrico
authors.initials: E
authors.lastname: Santamato
mesh_terms: D003198:Computer Simulation; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007909:Lenses; D008027:Light; D015233:Models, Statistical; D016011:Normal Distribution; D012542:Scattering, Radiation