Dynamics of Raman instabilities using chirped laser pulses

Jérôme Faure (1) , J.R. Marques (1) , Victor Malka (1) , François Amiranoff (1) , Z. Najmudin (2) , B. Walton (2) , Jean-Philippe Rousseau (3) , S. Ranc (3) , A. Solodov (4) , P. Mora (4)

1 LULI - Laboratoire pour l'utilisation des lasers intenses
2 Blackett Laboratory
3 LOA - Laboratoire d'optique appliquée
4 CPHT - Centre de Physique Théorique [Palaiseau]

Time resolved measurements of the growth of Raman instabilities were performed using a picosecond chirped laser pulse. It was observed experimentally that for a short laser pulse (<10 ps), forward and 30° Raman scattering occur at the back of the pulse. The growth of the instabilities was found to be independent of the sign of the chirp. In addition, a simple temporal model was developed and shows good agreement with the experimental results. This model also indicates that the plasma wave driven by forward Raman scattering is severely damped in the case of pulses longer than a few picoseconds. Damping by the modulational instability is compatible with the experimental results.

Domains: Optics [physics.optics]

Jérôme Faure, J.R. Marques, Victor Malka, François Amiranoff, Z. Najmudin, et al.. Dynamics of Raman instabilities using chirped laser pulses. Physical Review E : Statistical, Nonlinear, and Soft Matter Physics, 2001, 63 (6), pp.065401. ⟨10.1103/PhysRevE.63.065401⟩. ⟨hal-00519019⟩