Self-collimation in liquid surface waves propagating over a bottom with periodically drilled holes

Liquid surface waves propagating over a bottom with periodically drilled holes are studied experimentally and theoretically. Point source waves are generated in the center of the array of the periodically drilled holes in order to observe the evolvements of these waves. We successfully observe the self-collimation phenomenon in liquid surface waves. Band structures and constant-frequency surfaces are calculated, which can give a satisfactory interpretation of the experimental observations.