Acoustic band gaps in 2D liquid phononic crystals of rectangular structure

We present band structure results for a new two dimensional (2D) rectangular array geometry of water (mercury) cylinders of square cross section in a mercury (water) host. The results show that the water/mercury system, consisting of low-density cylinders in a high-density host, is the most favourable configuration for obtaining large acoustic gaps. Otherwise, only very small stop gaps can be found for the mercury/water systems. For a given cylinder width value, the lowest band gap may not always have the maximum width. but at some value in both systems the lowest band gap will always have the largest width. The differences in the case of circular cylinders are also discussed.