title: Efficient beam converter for the generation of high-power femtosecond vortices.
abstract: We describe an optical beam converter for an efficient transformation of Gaussian femtosecond laser beams to single- or double-charge vortex beams. 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.
authors.affiliation: Laser Physics Centre, Research School of Physics and Engineering, The Australian National University,Canberra ACT 0200, Australia. vgs124@physics.anu.edu.au
authors.forename: Vladlen G
authors.initials: VG
authors.lastname: Shvedov
authors.forename: Cyril
authors.initials: C
authors.lastname: Hnatovsky
authors.forename: Wieslaw
authors.initials: W
authors.lastname: Krolikowski
authors.forename: Andrei V
authors.initials: AV
authors.lastname: Rode
mesh_terms: D000669:Amplifiers, Electronic; D016880:Anisotropy; D003198:Computer Simulation; D004867:Equipment Design; D007834:Lasers; D016011:Normal Distribution; D055095:Optics and Photonics; D009991:Oscillometry / Q000379:methods; D013997:Time Factors