2019 journal article

Extremely Asymmetrical Acoustic Metasurface Mirror at the Exceptional Point

PHYSICAL REVIEW LETTERS, 123(21).

By: X. Wang *, X. Fang *, D. Mao *, Y. Jing n & Y. Li*

TL;DR: This work theoretically and experimentally demonstrate a non-Hermitian acoustic metasurface mirror featuring extremely asymmetrical reflection at the exception point, and it paves the way for identifying new mechanisms and functionalities for wave manipulation. (via Semantic Scholar)
Source: Web Of Science
Added: December 16, 2019

Previous research has attempted to minimize the influence of loss in reflection- and transmission-type acoustic metasurfaces. This Letter shows that, by treating the acoustic metasurface as a non-Hermitian system and by harnessing loss, unconventional wave behaviors that do not exist in lossless metasurfaces can be uncovered. Specifically, we theoretically and experimentally demonstrate a non-Hermitian acoustic metasurface mirror featuring extremely asymmetrical reflection at the exception point. As an example, the metasurface mirror is designed to have high-efficiency retroreflection when the wave comes from one side and near-perfect absorption when the wave comes from the opposite side. This work marries conventional gradient index metasurfaces with the exceptional point from non-Hermitian systems, and it paves the way for identifying new mechanisms and functionalities for wave manipulation.