title: Nonlinear optical catastrophe from a smooth initial beam.
abstract: We observed an optical cusp diffraction catastrophe with an initially smooth but elongated Gaussian beam with an aspect ratio of 2:1. Nonlinear and linear diffraction regimes account for the near-field elliptical annulus and the far-field spatially complex astroid.
authors: A M
authors: AM
authors: Deykoon
authors: M S
authors: MS
authors: Soskin
authors: G A
authors: GA
authors: Swartzlander