Phys.org November 10, 2020
The concept of impedance matching has been established in electrical, acoustic, and optical engineering to maximize energy transmission from a source through a media. However, existing design of acoustic impedance matching, which extends exactly by a quarter wavelength, sets a fundamental limit of narrowband transmission. An international team of researchers (China, USA – MIT, Harvard University, Duke University, South Korea, Denmark, Canada, Scotland, Germany) has shown that a class of bioinspired metagel impedance transformers can overcome this limit. The transformer embeds a two-dimensional metamaterial matrix of steel cylinders into hydrogel. Using experimental data of the biosonar from the Indo-Pacific humpback dolphin, they demonstrated through theoretical analysis that broadband transmission is achieved when the bioinspired acoustic impedance function is introduced. The metagel device offers efficient implementation in broadband underwater ultrasound detection with the benefit of being soft and tunable. The research paves a way for designing next-generation broadband impedance matching devices in diverse wave engineering…read more. Open Access TECHNICAL ARTICLEÂ 1 , 2Â TECHNICAL ARTICLE
A design of BMIT based on dolphin’s structure…. Credit: Science Advances 30 Oct 2020: Vol. 6, no. 44, eabb3641