We study numerically the change in characteristic sizes of light bullet’s (LB’s) high intensity region and the energy localized in it during filamentation of femtosecond mid-IR wave packet in LiF under the conditions of anomalous group velocity dispersion. It is found that in the process of LB’s propagation, the duration and diameter of a region with an intensity above 50 TW/cm<sup>2</sup> , as well as the amount of energy contained in this region, vary with distance. General character of the process of light bullet’s formation in different dielectric media allows to extend obtained results to the transfer of high-density energy in atmosphere.
The Supercontinuum (SC) generation during femtosecond laser pulse filamentation with various central wavelengths
in fused silica is investigated by numerical solution of nonlinear Schroedinger equation. Material dispersion of the
medium is considered due to Sellmeier formula. Nonmonotonic dependence of spectral intensity on wavelength in
anti-Stokes wing for anomalous group velocity dispersion (GVD) region (λ<sub>0</sub> = 1900 nm) was found. There is a local
minimum in SC spectrum from 800 nm to 1200 nm, and there is also a local maximum in SC spectrum from 400 nm
to 700 nm. We suppose such modification of pulse spectrum during filamentation process to be caused by
interference modulation of SC spectrum in presence of anomalous GVD.
Proc. SPIE. 6733, International Conference on Lasers, Applications, and Technologies 2007: Environmental Monitoring and Ecological Applications; Optical Sensors in Biological, Chemical, and Engineering Technologies; and Femtosecond Laser Pulse Filamentation
The feasibility of a microwave waveguide made of plasma channels under laser pulse filamentation is discussed. The
necessary channel bunch configuration is achieved by initial intensity modulation of a femtosecond pulse. Estimations
are given for wavelength of the microwave radiation and for parameters of the plasma channels configuration.