The self-focusing of ultra short optical pulses in a nonlinear medium with normal (i.e., negative) group-velocity dispersion is investigated. By using a combination of various techniques like virial-type arguments and self-similar transformations, we obtain strong evidence suggesting that a pulse propagating in a nonlinear medium with normal dispersion will not collapse to a singularity in the transverse diffraction plane. It is explicitly shown that the pulse spreads out along the ''time-direction'' and ultimately splits up. The analytical results are supported by direct numerical solutions.
Physica Scripta, 1996, Vol T67, p. 17-20
Optik og sensorsystemer
Main Research Area:
International Conference on Complex Dynamics in Spatially Extended Systems, 1996