title: Effect of electron heating on self-induced transparency in relativistic-intensity laser-plasma interactions.
abstract: The effective increase of the critical density associated with the interaction of relativistically intense laser pulses with overcritical plasmas, known as self-induced transparency, is revisited for the case of circular polarization. A comparison of particle-in-cell simulations to the predictions of a relativistic cold-fluid model for the transparency threshold demonstrates that kinetic effects, such as electron heating, can lead to a substantial increase of the effective critical density compared to cold-fluid theory. These results are interpreted by a study of separatrices in the single-electron phase space corresponding to dynamics in the stationary fields predicted by the cold-fluid model. It is shown that perturbations due to electron heating exceeding a certain finite threshold can force electrons to escape into the vacuum, leading to laser pulse propagation. The modification of the transparency threshold is linked to the temporal pulse profile, through its effect on electron heating.
authors.affiliation: Max Planck Institute for the Physics of Complex Systems, D-01187 Dresden, Germany. evangelos.siminos@gmail.com
authors.forename: E
authors.initials: E
authors.lastname: Siminos
authors.forename: M
authors.initials: M
authors.lastname: Grech
authors.forename: S
authors.initials: S
authors.lastname: Skupin
authors.forename: T
authors.initials: T
authors.lastname: Schlegel
authors.forename: V T
authors.initials: VT
authors.lastname: Tikhonchuk
mesh_terms: D003198:Computer Simulation; D004583:Electrons; D006358:Hot Temperature; D007834:Lasers; D008956:Models, Chemical; D058626:Plasma Gases / Q000737:chemistry* / Q000528:radiation effects*; D011789:Quantum Theory; D011829:Radiation Dosage; D012031:Refractometry / Q000379:methods*
chemical_list: D058626:Plasma Gases