title: Decay of femtosecond laser-induced plasma filaments in air, nitrogen, and argon for atmospheric and subatmospheric pressures.
abstract: The temporal evolution of a plasma channel at the trail of a self-guided femtosecond laser pulse was studied experimentally and theoretically in air, nitrogen (with an admixture of ∼3% O_{2}), and argon in a wide range of gas pressures (from 2 to 760 Torr). Measurements by means of transverse optical interferometry and pulsed terahertz scattering techniques showed that plasma density in air and nitrogen at atmospheric pressure reduces by an order of magnitude within 3-4 ns and that the decay rate decreases with decreasing pressure. The argon plasma did not decay within several nanoseconds for pressures of 50-760 Torr. We extended our theoretical model previously applied for atmospheric pressure air plasma to explain the plasma decay in the gases under study and to show that allowance for plasma channel expansion affects plasma decay at low pressures.
authors: Moscow Institute of Physics and Technology, Dolgoprudny 141700, Russia.
authors: N L
authors: NL
authors: Aleksandrov
authors: Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod 603950, Russia.|University of Nizhny Novgorod, Nizhny Novgorod 603950, Russia.
authors: S B
authors: SB
authors: Bodrov
authors: University of Nizhny Novgorod, Nizhny Novgorod 603950, Russia.
authors: M V
authors: MV
authors: Tsarev
authors: Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod 603950, Russia.
authors: A A
authors: AA
authors: Murzanev
authors: Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod 603950, Russia.
authors: Yu A
authors: YA
authors: Sergeev
authors: Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod 603950, Russia.
authors: Yu A
authors: YA
authors: Malkov
authors: Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod 603950, Russia.
authors: A N
authors: AN
authors: Stepanov