BAND-GAP ENGINEERING IN PERIODIC ELASTIC COMPOSITES

Periodic elastic composites can give rise to complete band gaps in whi ch vibrations, sound, and phonons are forbidden. This is of interest f or applications such as creation of vibrationless environment and impr ovements in transducers, as well as for pure physics related to locali zed vibrations and phonons. We present rudimentary ideas of the ''band -gap engineering'' necessary for designing suitable frequency gaps. Th is is illustrated by means of acoustic band structures, computed for p eriodic, binary composites of long, elastic cylinders that form a hexa gonal lattice.