Abstract:

Nonlinear waves with basic wave numbers, k1 and k2, are simultaneously excited via two-frequency parametric excitation of a fluid surface. Three new multiwave states are observed: (1) A superlattice state composed of k1 and k2 whose relative orientation is governed by a temporal resonance condition, (2) a superlattice built entirely of wave numbers k1 and k1/2, and (3) a state composed of wave numbers of lengths k1 and k2 that are uncorrelated in both space and time. The three states exhibit interesting temporal as well as spatial behavior and are observed in a variety of frequency combinations.