title: Dynamic behavior of postfilamentation Raman pulses.
abstract: We report on the postfilamentation behavior of a Stokes pulse created from intense and collimated ultrashort pulses propagating in air. A systematic analysis of the pulse propagation revealed that the redshifted Raman pulse produced during filamentation had a larger divergence than the postfilamentation intense pump pulse. Also, the analysis of the far-field Stokes transverse ring revealed that the intensity in this ionization-free light channel is still sufficiently high to induce stimulated Raman scattering after ionization had ended. This behavior further extends the potential of filamentation to remotely induce third-order nonlinearities.
authors: Centre d’Optique, Photonique et Laser et Département de physique, de génie physique et d’optique, Université Laval, Québec, Canada. jfdaigle2@yahoo.ca
authors: Jean-François
authors: JF
authors: Daigle
authors: Tie-Jun
authors: TJ
authors: Wang
authors: Sima
authors: S
authors: Hosseini
authors: Shuai
authors: S
authors: Yuan
authors: Gilles
authors: G
authors: Roy
authors: See Leang
authors: SL
authors: Chin