Extreme Capillary Wave Events Under Parametric Excitation

Extreme wave events have recently been discovered in the parametrically excited surface ripples. When a fluid container is periodically shaken in the vertical direction, capillary-gravity waves are excited at the frequency of the first subharmonic of the driving frequency. Such waves appear to be unstable to the amplitude modulation. The modulation instability leads to the destruction of waves into ensembles of interacting oscillating solitons. Presented laboratory studies suggest a quasi-particle nature of the parametrically driven surface ripples. The wave field dynamics is determined by the oscillon interactions, including their merger, annihilation, and collisions. Collisions of the same phase oscillons lead to generation of the extreme events, or capillary rogue waves.