We experimentally demonstrate concatenation of several plasma filaments left in the wake of powerful femtosecond laser pulse propagating in the atmosphere [1]. This technique allows generation of a long "broken" plasma wire in air. Lifetime of these plasma filaments is extended by more than an order of magnitude by using an external nanoseconds laser [2]. We reveal the physical mechanism behind the prolongation of plasma life time and demonstrate the preferential conditions for lifetime extension. The combination of these two methods will allow generation of long, coexisting plasma channels with high electron density. This approach may pave the way towards many of the potential applications of femtosecond beam filamentation previously proposed in the literature.

References

[1] J. Papeer, R. Bruch, E. Dekel, O.Pollak, M.Botton, Z. Henis & A. Zigler,  " Generation of concatenated long high-density plasma channels in air by a single femtosecond laser pulse," Applied Physics Letters, 107, 124102 (2015).

[2] J. Papeer,  M. Botton, D. Gordon, P. Sprangle, A. Zigler & Z. Henis,  "Extended lifetime of high density plasma filament generated by a dual femtosecond–nanosecond laser pulse in air" New Journal of Physics, 16(12), 123046, (2014).