期刊
SCIENCE ADVANCES
卷 7, 期 45, 页码 -出版社
AMER ASSOC ADVANCEMENT SCIENCE
DOI: 10.1126/sciadv.abj1198
关键词
-
资金
- National Key Ramp
- D Program of China [2017YFA0303700]
- National Natural Science Foundation of China [11634006, 11674119, 11690030, 11690032, 11374157, 81127901]
- National Science Foundation EFRI program [1641069]
- Air Force Office of Scientific Research MURI program [FA9550-18-1-0379]
- Simons Foundation
- Vannevar Bush Faculty Fellowship
- Innovation Special Zone of National Defense Science and Technology
- Priority Academic Program Development of Jiangsu Higher Education Institutions
- Emerging Frontiers & Multidisciplinary Activities
- Directorate For Engineering [1641069] Funding Source: National Science Foundation
This study overcomes the limitations of traditional acoustic systems by implementing spatiotemporally modulated acoustic metamaterials to support nonreciprocal sound steering, showcasing efficient nonreciprocal sound manipulation through dynamic control of acoustic impedance.
In linear, lossless, time-invariant, and nonbiased acoustic systems, mode transitions are time reversible, consistent with Lorentz reciprocity and implying a strict symmetry in space-time for sound manipulation. Here, we overcome this fundamental limitation by implementing spatiotemporally modulated acoustic metamaterials that support nonreciprocal sound steering. Our mechanism relies on the coupling between an ultrathin membrane and external biasing electromagnetic fields, realizing programmable dynamic control of the acoustic impedance over a motionless and noiseless platform. The fast and flexible impedance modulation of our metamaterial imparts an effective unidirectional momentum in space-time to realize nonreciprocal transitions in k-omega space between different diffraction modes. On the basis of these principles, we demonstrate efficient nonreciprocal sound steering, showcasing unidirectional evanescent wave conversion and nonreciprocal upconversion focusing. More generally, our metamaterial platform offers opportunities for generation of nonreciprocal Bloch waves and extension to other domains, such as non-Hermitian topological and parity-time symmetric acoustics.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据