title: Nonlocal resonances in weak turbulence of gravity-capillary waves.
abstract: We report a laboratory investigation of weak turbulence of water surface waves in the gravity-capillary crossover. By using time-space-resolved profilometry and a bicoherence analysis, we observe that the nonlinear processes involve three-wave resonant interactions. By studying the solutions of the resonance conditions, we show that the nonlinear interaction is dominantly one dimensional and involves collinear wave vectors. Furthermore, taking into account the spectral widening due to weak nonlinearity explains why nonlocal interactions are possible between a gravity wave and high-frequency capillary ones. We observe also that nonlinear three-wave coupling is possible among gravity waves, and we raise the question of the relevance of this mechanism for oceanic waves.
authors.affiliation: Université Grenoble Alpes, LEGI, CNRS, F-38000 Grenoble, France and Institut Universitaire de France, 103, Boulevard Saint Michel, F-75005 Paris, France.
authors.forename: Quentin
authors.initials: Q
authors.lastname: Aubourg
authors.affiliation: Université Grenoble Alpes, LEGI, CNRS, F-38000 Grenoble, France and Institut Universitaire de France, 103, Boulevard Saint Michel, F-75005 Paris, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Mordant