Optical wave turbulence and the condensation of light

Abstract

In an optical experiment, we report a wave turbulence regime that, starting\nwith weakly nonlinear waves with randomized phases, shows an inverse cascade of\nphotons towards the lowest wavenumbers. We show that the cascade is induced by\na six-wave resonant interaction process and is characterized by increasing\nnonlinearity. At low wavenumbers the nonlinearity becomes strong and leads to\nmodulational instability developing into solitons, whose number is decreasing\nfurther along the beam.\n