Engineers have designed a new type of artificial material – a metamaterial – able to handle a wide range of acoustic wave device using a single very simple.
The feat made the cover of the prestigious journal Journal of Applied Physics .
Optical metamaterials have been widely studied for applications such as invisibility cloaks and perfect lenses .
Although acoustic waves and electromagnetic waves are very different, the basic principles of optical metamaterials apply to acoustic metamaterials.
The artificial structures, known as metamaterials, are built on standards that bend the acoustic wave, directing it to a single point.Then, the acoustic wave is reoriented to form a beam which can be wider or narrower depending on the direction of displacement.
The device – a technically sound modifier opening – was built with crystals phononic contribution with variable refractive index, a fancy name for an array of steel pins embedded in epoxy, carefully calculated according to a pattern.The obstacles – the steel pins – slows down the acoustic wave, causing it to compose curved beams.
According to Sz-Chin Steven Lin, creator of the new device, although other types of acoustic metamaterials can also focus or blur an acoustic beam, the new device has the advantage of being small and having a high energy conservation.Today, scientists and physicians need several transducers of different sizes to produce acoustic waves at different apertures.It is something like having to change the lens of a camera to change the lens opening.
With this new metamaterial acoustic the desired aperture can be easily obtained only by changing the modifier opening connected to the acoustic transducer.The device must also allow the development of new therapies high ultrasonic intensity, more precise and more efficient.This non-invasive technique of heat can be used to combat a variety of cancers and neurological diseases.