Efficient generation of third harmonic radiation in air filaments: A revisit

Yi Liu (1) , Magali Durand (1, 2) , Aurélien Houard (1) , Benjamin Forestier (1) , Arnaud Couairon (3) , André Mysyrowicz (1)

1 LOA - Laboratoire d'optique appliquée
2 ONERA - The French Aerospace Lab [Châtillon]
3 CPHT - Centre de Physique Théorique [Palaiseau]

In this paper we revisit the third harmonic generation from a femtosecond laser filament in air and its significant enhancement (~ 100 times) with a intercepting pump pulse, which has been reported very recently. The enhanced third harmonic is studied as a function of the pulse polarization, time delay between the pump and signal pulses, laser pulse energy, etc. We provide an explanation for the enhancement of third harmonic based on a quenching of interference effects present near filamentation threshold. Simulations based on a two-color propagation code reproduce well the experimental observations and confirm our interpretation.

Domains: Optics [physics.optics]

Yi Liu, Magali Durand, Aurélien Houard, Benjamin Forestier, Arnaud Couairon, et al.. Efficient generation of third harmonic radiation in air filaments: A revisit. Optics Communications, 2011, 284 (19), pp.4706. ⟨10.1016/j.optcom.2011.05.050⟩. ⟨hal-00852025⟩