Open AccessNonlinear generation of broadband polarisation vortices
Author(s) -
Siddharth Ramachandran,
C. Smith,
Poul Kristensen,
Péter Balling
Publication year - 2010
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.18.023212
Subject(s) - optics , raman scattering , polarization (electrochemistry) , optical vortex , wavelength , vortex , nonlinear optics , laser , light beam , materials science , physics , scattering , beam (structure) , raman spectroscopy , chemistry , thermodynamics
Polarisation-vortex beams over a broad wavelength region are generated by nonlinear transformation of a radially-polarized mode in a specially-designed optical fiber. The beams are produced by stimulated Raman scattering from 20-ns 1064-nm laser pulses, and up to the 4th order Stokes shift is observed. Measurements of polarization-selected intensity profiles of individual Stokes components show that the generated light maintains the desired spatial intensity distribution and radial polarization of the pump mode. At the highest pump power, 300 W, the process creates a coherent vortex beam from 1064 nm to 1310 nm, which is a span of nearly 250 nm.