Confining and slowing airborne sound with a corrugated metawire

In this letter we present a theoretical study on the acoustic wave propagation along a periodically corrugated perfect rigid wire surrounded by air. It is shown how acoustic surface waves (ASWs) can be engineered with their propagation properties controlled by geometrical means. These highly localized ASWs give rise to strong acoustical field confinement along the wire, whereas the slowing down of sound decelerate the group velocity down to zero. What is believed to be a promising feature of these low-loss propagation properties is the ability to tune sensing and screening applications with good transducer coupling. (C) 2008 American Institute of Physics.