title: Vector spherical quasi-Gaussian vortex beams.
abstract: Model equations for describing and efficiently computing the radiation profiles of tightly spherically focused higher-order electromagnetic beams of vortex nature are derived stemming from a vectorial analysis with the complex-source-point method. This solution, termed as a high-order quasi-Gaussian (qG) vortex beam, exactly satisfies the vector Helmholtz and Maxwell's equations. It is characterized by a nonzero integer degree and order (n,m), respectively, an arbitrary waist w(0), a diffraction convergence length known as the Rayleigh range z(R), and an azimuthal phase dependency in the form of a complex exponential corresponding to a vortex beam. An attractive feature of the high-order solution is the rigorous description of strongly focused (or strongly divergent) vortex wave fields without the need of either the higher-order corrections or the numerically intensive methods. Closed-form expressions and computational results illustrate the analysis and some properties of the high-order qG vortex beams based on the axial and transverse polarization schemes of the vector potentials with emphasis on the beam waist.
authors.affiliation: Los Alamos National Laboratory, MS D429, Los Alamos, New Mexico 87545, USA.
authors.forename: F G
authors.initials: FG
authors.lastname: Mitri
mesh_terms: D000465:Algorithms; D003198:Computer Simulation; D004574:Electromagnetic Fields; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008027:Light; D008962:Models, Theoretical; D012542:Scattering, Radiation