title: Resonant self-trapping of high intensity Bessel beams in underdense plasmas.
abstract: We present a comprehensive report based on recent work [Phys. Rev. Lett. 84, 3085 (2000)] on resonant self-trapping and enhanced absorption of high power Bessel beams in underdense plasmas. The trapping resonance is strongly dependent on initial gas pressure, Bessel-beam geometry, and laser wavelength. Analytic estimates, and simulations using a one-dimensional Bessel-beam-plasma interaction code consistently explain the experimental observations. These results are for longer, moderate intensity pulses where the self-trapping channel is induced by laser-heated plasma thermal pressure. To explore the extension of this effect to ultrashort, intense pulsed Bessel beams, we perform propagation simulations using the code WAKE [Phys. Rev. E 53, R2068 (1996)]. We find that self-trapping can occur as a result of a plasma refractive index channel induced by the combined effects of relativistic motion of electrons and their ponderomotive expulsion.
authors.affiliation: Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742, USA.
authors.forename: J
authors.initials: J
authors.lastname: Fan
authors.forename: E
authors.initials: E
authors.lastname: Parra
authors.forename: K Y
authors.initials: KY
authors.lastname: Kim
authors.forename: I
authors.initials: I
authors.lastname: Alexeev
authors.forename: H M
authors.initials: HM
authors.lastname: Milchberg
authors.forename: J
authors.initials: J
authors.lastname: Cooley
authors.forename: T M
authors.initials: TM
authors.lastname: Antonsen