DURHAM, N.C. -- Researchers at Duke University and Aalto University (Finland) have constructed a "meta-mirror" device capable of perfectly reflecting sound waves in any direction. The ...

There may be new hope for people with noisy neighbors. Scientists at MIT have developed a method of using thin sheets of fabric to either cancel or block sound – in the latter case, the racket even ...

The interface between two facets of an artificial material known as a “Weyl phononic crystal” can not only negatively refract an airborne sound wave, it does so without reflecting it at all. This ...

Acoustic waves in gases, liquids, and solids usually travel at an almost constant speed of sound. So-called rotons are an exception: their speed of sound changes significantly with the wavelength, and ...

Researchers have succeeded in controllably propagating sound waves along the boundaries of topological metamaterials using a modulation technique that breaks time-reversal symmetry. This feat, which ...