Localization of water surface waves in a heterostructure channel with corrugated sidewalls

This paper describes the fabrication of a water channel heterostructure by combining two types of periodic sidewalls with different duty ratios. This enables the manipulation and localization of water surface waves in bands that are traditionally inaccessible. It is well known that such forbidden bands can be created by the introduction of periodicity, in which the wave propagation is efficiently attenuated when the Bragg condition is satisfied. Through experiments and simulations, we show that an extraordinary transmission arises in the bandgap after two types of periodic channels are combined, even though they have similar forbidden bands. Waves that cannot travel along each channel then begin to propagate along the heterostructure channel. The measured surface amplitude of the water waves indicates that the localization around the interface of two periodic structures is responsible for the extraordinary transmission. The localized energy of water waves shifts according to the distance between the two periodic structures, and the localization and transmission disappear at certain distances. The measurement and analysis of this intriguing phenomenon of water wave manipulation will benefit applications in the collection and utilization of water wave energy.