title: Generation of spirally polarized propagation-invariant beam using fiber microaxicon.
abstract: We present here a fiber microaxicon (MA)based method to generate spirally polarized propagation-invariant optical beam. MA chemically etched in the tip of a two-mode fiber efficiently converts the generic cylindrically polarized vortex fiber mode into a spirally polarized propagation-invariant (Bessel-type) beam via radial dependence of polarization rotation angle. The combined roles of helico-conical phase and nonparaxial propagation in the generation and characteristics of the output beam from the fiber MA are discussed.
authors.affiliation: School of Physics, University of Hyderabad, Hyderabad 500046, India.
authors.forename: Geo M
authors.initials: GM
authors.lastname: Philip
authors.forename: Nirmal K
authors.initials: NK
authors.lastname: Viswanathan