Acoustic device could cloak objects, jettison loud sounds
Z. Yang et al/Physical Review Letters 2015
An array of miniature turntables could offer a powerful new way to control the flow of sound.
The proposed device, reported in the March 20 Physical Review Letters, would channel sound waves in a protected one-way thoroughfare along its edge. The structure is an acoustic version of a hotly researched class of materials called topological insulators. As the name suggests, these materials are primarily insulators, yet they efficiently transport electrons along their periphery.
The new study “shows that this rather exotic physical property can emerge in something as familiar as sound propagation,” says Steven Cummer, an electrical engineer at Duke University who was not involved in the work.
For now, the design requires many moving parts and manipulates only a narrow swath of sound frequencies. But a similar structure could eventually allow engineers to redirect loud noises out of a