Experimental realization of broadband control of water-wave-energy amplification in chirped arrays

Water waves in natural environments are typically broadband, nonlinear, and dynamic phenomena. Taking concepts developed for slow light in optics, we address the challenge of designing arrays to control the spatial distribution of wave energy, and amplify specific frequencies from within target frequency bands at individual locations. Meter-scale wave-flume experiments, in which incident waves interact with a chirped array of eight vertical cylinders, demonstrate significant amplifications over a broad frequency range, as predicted numerically and theoretically.