Triggering filamentation using turbulence
  We study the triggering of single filaments due to turbulence in the beam path for a laser of power below the filamenting threshold. Turbulence can act as a switch between the beam not filamenting and producing single filaments. This 'positive' effect of turbulence on the filament probability, combined with our observation of off-axis filaments suggests the underlying mechanism is modulation instability caused by transverse perturbations. We hereby experimentally explore the interaction of modulation instability and turbulence, commonly associated with multiple-filaments, in the single-filament regime. 
D. Eeltink, N. Berti, N. Marchiando, S. Hermelin, J. Gateau, M.   Brunetti, J.P. Wolf, and J. Kasparian
physics.optics nlin.PS