Elastic band gaps in a fcc lattice of mercury spheres in aluminum

Elastic waves propagating in a periodic system consisting of mercury spheres arranged in a fcc lattice and surrounded by aluminum have been studied using the layer-multiple-scattering method. The band structure shows wide elastic band gaps along certain high-symmetry directions. For filling ratios of mercury spheres around 8.2%, there is a narrow full band gap with maximum width of the gap over mid-gap frequency of 2.5%. The full band gap can be further enhanced by using a heterostructure containing seven slabs of different sizes of mercury spheres and can be as wide as 14.4%.