title: Spiral laser beams in inhomogeneous media.
abstract: Explicit solutions of the inhomogeneous paraxial wave equation in a linear and quadratic approximation are applied to wave fields with invariant features, such as oscillating laser beams in a parabolic waveguide and spiral light beams in varying media. A similar effect of superfocusing of particle beams in a thin monocrystal film, harmonic oscillations of cold trapped atoms, and motion in magnetic field are also mentioned.
authors.affiliation: School of Mathematical and Statistical Sciences, Arizona State University, Tempe, Arizona 85287-1804, USA.
authors.forename: Alex
authors.initials: A
authors.lastname: Mahalov
authors.forename: Erwin
authors.initials: E
authors.lastname: Suazo
authors.forename: Sergei K
authors.initials: SK
authors.lastname: Suslov