KAUST hybrid elastics research develops new metamaterial
Hybrid elastics research at King Abdullah University of Science and Technology (KAUST), recently featured in Nature Middle East, has developed a new type of metamaterial.
The research, carried out in conjunction with Hong Kong University of Science and Technology (HKUST) and Soochow University, China, discusses a design of an elastic material that contains several resonances within its structure.
Ying Wu, Assistant Professor, Mathematical and Computational Science and Engineering, HKUST faculty Ping Sheng and Zhao- Qing Zhang and Yun Lai of Soochow discovered that the material has unusual acoustic properties.
Unusual characteristics
At certain frequencies, the elastic material only transmits pressure waves and becomes "fluid-like," blurring the distinction between a fluid and a solid. At other frequencies, however, the material displays "super anisotropy" (directional dependency), observed by the directionality of compression waves and shear waves movement.
"The most intriguing property of the metamaterial is that it can produce a band which is not only 'super-anisotropic' but also 'negative'. Neither of them is easy to achieve, but we have done it simultaneously," explained Wu.
These unusual traits have no similar examples in conventional solids and could lead to novel applications in wave polarizers, transformation acoustics, controlling elastic and seismic waves, and wave imaging and confinement.
Supporting international collaborations
Initial research into the design concept began four years ago in Hong Kong after Wu published a paper in Physcial Review B, however it wasn't until she moved to KAUST in 2009 that serious work began.
"The best thing about KAUST is that it provides sufficient support and I still have the autonomy. I have the freedom of deciding what to do without interruptions and was even able to bring the co-authors to Saudi Arabia."
Further research into the metamaterial is ongoing and future experimental work with Wu's collaborators is being discussed.