Femtosecond filamentation in air at low pressures. Part II: Laboratory experiments

Grégoire Méchain (1) , Thomas Olivier (1) , Michel A. Franco (1) , Arnaud Couairon (2) , Bernard Prade (1) , André Mysyrowicz (1)

1 LOA - Laboratoire d'optique appliquée
2 CPHT - Centre de Physique Théorique [Palaiseau]

We present experimental studies of filamentation of a femtosecond laser pulse in air at low pressures. The evolution of the filament has been studied by measuring along the propagation axis the conductivity and the sub-THz emission from the plasma channel. We show experimentally that the filamentation process occurs at pressures as low as 0.2 atm in agreement with numerical simulations. Experimental and numerical results [A. Couairon, M. Franco, G. Méchain, T. Olivier, B. Prade, A. Mysyrowicz, Opt. Commun., submitted for publication] are compared and the possible sources of discrepancy are discussed.

Keywords: filamentation; nonlinear optics

Domains: Optics [physics.optics]

Grégoire Méchain, Thomas Olivier, Michel A. Franco, Arnaud Couairon, Bernard Prade, et al.. Femtosecond filamentation in air at low pressures. Part II: Laboratory experiments. Optics Communications, 2006, 261 (2), pp.322-326. ⟨10.1016/j.optcom.2005.11.041⟩. ⟨hal-00461561⟩