Superscattering of water waves

Zijian Qin; Chao Qian; Lian Shen; Xiaoping Wang; Ido Kaminer; Hongsheng Chen; Huaping Wang

doi:10.1093/nsr/nwac255

Superscattering of water waves

Natl Sci Rev. 2022 Nov 10;10(7):nwac255. doi: 10.1093/nsr/nwac255. eCollection 2023 Jul.

Authors

Zijian Qin^{1

2}, Chao Qian^{3

2

4}, Lian Shen^{3

2}, Xiaoping Wang¹, Ido Kaminer⁵, Hongsheng Chen^{3

2

4}, Huaping Wang¹

Affiliations

¹ Key Laboratory of Ocean Observation-Imaging Testbed of Zhejiang Province, Institute of Marine Electronics Engineering, Ocean College, Zhejiang University, Hangzhou 310058, China.
² ZJU-Hangzhou Global Science and Technology Innovation Center, Key Lab. of Advanced Micro/Nano Electronic Devices & Smart Systems of Zhejiang, Zhejiang University, Hangzhou 310027, China.
³ ZJU-UIUC Institute, Interdisciplinary Center for Quantum Information, State Key Laboratory of Modern Optical Instrumentation, Zhejiang University, Hangzhou 310027, China.
⁴ Jinhua Institute of Zhejiang University, Zhejiang University, Jinhua 321099, China.
⁵ Department of Electrical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel.

Abstract

Inspired by the concept of superscattering in optics, we for the first time theoretically predict and experimentally demonstrate the superscattering phenomenon in water waves. The subwavelength superscatterer is constructed by multi-layered concentric cylinders with an inhomogeneous depth profile. The superscatterer breaks the long-held single-channel scattering limit by several times and thus significantly enhances the total scattering strength. The underlying mechanism originates from the near degeneracy of the resonances of multiple channels. We fabricate the superscatterer prototype and experimentally measure the near-field patterns, which are consistent with theoretical prediction and numerical simulation. Our study opens a new avenue to strengthen water-wave scattering and deepen the understanding in water waves, which can be useful for ocean energy harvesting and harbor protection.

Keywords: metamaterials; superscattering; water wave.