Spatiotemporal rogue events in optical multiple filamentation.
The transient appearance of bright spots in the beam profile of optical filaments formed in xenon is experimentally investigated. Fluence profiles are recorded with high-speed optical cameras at the kilohertz repetition rate of the laser source. A statistical analysis reveals a thresholdlike appearance of heavy-tailed fluence distributions together with the transition from single to multiple filamentation. The multifilament scenario exhibits near-exponential probability density functions, with extreme events exceeding the significant wave height by more than a factor of 10. The extreme events are isolated in space and in time. The macroscopic origin of these experimentally observed heavy-tail statistics is shown to be local refractive index variations inside the nonlinear medium, induced by multiphoton absorption and subsequent plasma thermalization. Microscopically, mergers between filament strings appear to play a decisive role in the observed rogue wave statistics.
Max-Born-Institut, Max-Born-Straße 2A, 12489 Berlin, Germany.
Simon
S
Birkholz
Max-Born-Institut, Max-Born-Straße 2A, 12489 Berlin, Germany.
Erik T J
ET
Nibbering
Weierstrass Institute for Applied Analysis and Stochastics, Mohrenstraße 39, 10117 Berlin, Germany.
Carsten
C
Brée
Max Planck Institute for the Physics of Complex Systems, 01187 Dresden, Germany, and Institute of Condensed Matter Theory and Optics, Friedrich Schiller University, 07743 Jena, Germany.
Stefan
S
Skupin
Institut für Quantenoptik, Leibniz-Universität Hannover, Welfengarten 1, 30167 Hannover, Germany.
Ayhan
A
Demircan
Physics Department, Tampere University of Technology, 33101 Tampere, Finland.
Goëry
G
Genty
Max-Born-Institut, Max-Born-Straße 2A, 12489 Berlin, Germany and Optoelectronics Research Centre, Tampere University of Technology, 33101 Tampere, Finland.
Günter
G
Steinmeyer