title: Generation of optical vortex beams by nonlinear wave mixing.
abstract: It is shown that optical vortex beams can be generated from a non-vortex fundamental beam by an optical frequency conversion process taking place within a twisted nonlinear photonic crystal. This is done without any first-order (linear) refractive optics. Through such a proposed structure, all-optical switching of vortices with different helicities is made possible, as well as the simultaneous application of counter-rotating vortex beams of different frequencies.
authors: School of Electrical Engineering, Wolfson Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel.
authors: Alon
authors: A
authors: Bahabad
authors: Ady
authors: A
authors: Arie
mesh_terms: D003198:Computer Simulation; D008027:Light; D008029:Lighting / Q000379:methods*; D008962:Models, Theoretical; D017711:Nonlinear Dynamics; D012542:Scattering, Radiation