Scientists have unveiled a so-called ‘cloak of silence’ which can make objects such as a house impervious to sound waves.

The technology has been reported in the New Journal of Physics and could be used for many purposes including the sound-proofing of homes and improving the acoustics in concert halls.

“The mathematics behind cloaking has been known for several years,” said Professor John Pendry, an expert in cloaking from the Imperial College London. “What hasn’t been available for sound is the sort of materials you need to build a cloak out of.”

The Spanish team who is behind the new research has discovered what they believe to be the key to the cloak, “Sonic Crystals”. These crystals are an artificial composite known as “meta-materials” and would be used to channel sound around an object, much like how water flows around a rock in a stream.

“The idea of acoustic cloaking is to deviate the sounds waves around the object that has to be cloaked,” said Jose Sanchez-Dehesa, one of the researchers behind the new work.

“It’s not an unrealistic blueprint – it doesn’t demand that we do extraordinary things,” said Pendry. “This is something that can easily be manufactured.”

Source:
BBC News