Mode-selecting acoustic filter by using resonant tunneling of two-dimensional double phononic crystals

In this letter, we investigated the resonant tunneling of elastic waves through double phononic potential barriers formed by two slabs of two-dimensional phononic crystals consisting of pure solid components. It is found that the resonant tunneling longitudinal waves can be distinguished easily from the resonant tunneling transverse waves. Thus, such double-barrier structures can be served as a mode-selecting acoustic filter, used to pick out the single longitudinal wave component or transverse wave component at a certain frequency.