AMALGAMATION OF INTERACTING LIGHT BEAMLETS IN KERR-TYPE MEDIA

The interaction of optical filaments in bulk self-focusing media is in vestigated theoretically and numerically. The nature of this interacti on is shown to vary with the incident individual powers and relative p hases of the beamlets. By means of virial arguments supported by numer ical results it is found that three distinct evolution regimes charact erize two in-phase interacting filaments: (i) When each filament has a power below N-c/4, where N-c is the critical self-focusing threshold for a single wave, both filaments disperse along their propagation axi s. (ii) When their respective powers lie between N-c/4 and N-c, they f use into a single central lobe that may self-focus until collapse, dep ending on their initial separation distance. The critical distance bel ow which a central lobe forms and collapses is estimated analytically. (iii) When their incident powers both exceed N,, initially separated filaments individually self-focus without mutual interaction. In contr ast to in-phase beamlets, two light cells with opposite phase are show n to never coalesce. The extension of the self-focusing dynamics to op tical filaments in bulk media with anomalous group-velocity dispersion is discussed. (C) 1997 Optical Society of America.