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arXiv · 1807.10887

Valley-projected edge modes observed in underwater sonic crystals

Yuanyuan Shen·Chunyin Qiu·Xiangxi Cai·Liping Ye·Jiuyang Lu·Manzhu Ke·Zhengyou Liu
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Abstract

Recently, the topological physics in acoustics has been attracting much attention. However, all the studies are aimed to elastic or airborne sound systems. Realizing topological insulators for underwater sound is of great importance, since water is another crucial sound medium in addition to solid and air. Here we report an experimental study on the valley-projected edge states for underwater sound. The edge states are directly observed in our ultrasound scanning experiments, together with a solid evidence for the valley-selective excitation. The experimental data agree well with our numerical results. Prospective applications can be anticipated, such as for underwater sound signal processing and ocean noise control.

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Yuanyuan Shen, Chunyin Qiu, Xiangxi Cai, Liping Ye, Jiuyang Lu, Manzhu Ke, Zhengyou Liu. 2018-07-28. Valley-projected edge modes observed in underwater sonic crystals. https://doi.org/10.1063/1.5049856

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