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 […]