title: Simulation of free-space optical guiding structure based on colliding gas flows.
abstract: Preformed plasma channels with parabolic radial density profiles enable the extended and stable optical guiding of high-intensity laser pulses. High-voltage discharge capillaries, commonly used for channel formation, have limited guiding length and opaque walls, complicating the diagnosis of the plasma within. This paper proposes a free-space gas channel produced by the collision of several gas flows. The collision of the gas flows forms an on-axis density depression surrounded by higher density walls. By offsetting the flows, we demonstrated the creation of what we believe is a novel vortex structure that exhibits a long-lived parabolic density profile. Once ionized, the resulting plasma density profile has a near-parabolic dependence appropriate for guiding. We then performed detailed two-dimensional (2D) fluid dynamics simulations to examine the properties and stability of the guiding structure.
authors.forename: D
authors.initials: D
authors.lastname: Kaganovich
authors.forename: J P
authors.initials: JP
authors.lastname: Palastro
authors.forename: Y-H
authors.initials: YH
authors.lastname: Chen
authors.forename: D F
authors.initials: DF
authors.lastname: Gordon
authors.forename: M H
authors.initials: MH
authors.lastname: Helle
authors.forename: A
authors.initials: A
authors.lastname: Ting