Bessel-modulated Gaussian beams with quadratic radial dependence

We describe a class of closed-form solutions of the paraxial wave equation whose transverse profile is a Gaussian function multiplied by a Bessel function, the argument of which is quadratic in the distance from the axis. Their characteristics are compared to those of Bessel-Gauss beams. Unlike the latter, these Bessel-modulated Gaussian beams propagate colinearly. They have interesting non-Gaussian features for certain values of their parameters, such as concentric rings of phase dislocation outside the waist plane or a flat axial profile. (C) 1999 Elsevier Science B.V. All rights reserved.