声学Pancharatnam-Berry几何相对于结构化的声音操纵
Wanyue Xiao1, Wenjian Kuang2, Sibo Huang3,4
1Department of Physics, City University of Hong Kong, Kowloon 999077, Hong Kong, China.
概括
研究人员在声学中展示了难以捉摸的几何相 (Pancharatnam-Berry相). 这一突破使得新的声学超表面和设备能够用于先进的声音操纵和应用.
科学领域:
- 声学和波浪物理学 波浪物理学
- 超材料和纳米光子学
- 几何阶段现象 几何阶段现象
背景情况:
- 阶段控制对于操纵声波至关重要,通常使用传播和共振阶段.
- 由于空中声波的性质,真实空间几何相或Pancharatnam-Berry (PB) 阶段在声学中很难实现.
研究的目的:
- 从理论和实验上证明PB阶段在不均的声波中出现的情况.
- 探索PB阶段的Janus属性及其在波面操纵的声学元表面中的应用.
- 扩展这种机制到自由空间结构化的声音,用于诸如声学q-plates等应用.
主要方法:
- 理论建模不均的声音波与不断变化的速度场.
- 使用表面声波的实验实现,以证明PB相及其Janus属性.
- 制造和测试声学Pancharatnam-Berry金属表面和声学q板.
主要成果:
- 通过速度场的极化演变成功地证明了声学系统中的PB相.
- 由于旋转动量锁定,发现了声学PB相的Janus属性.
- 开发了用于多功能波面操纵的声学PB超表面和用于旋拓电荷转换的声学q板.
结论:
- 这项工作在声学中引入了一种新型的声学相,即几何相 (PB相).
- 已经建立了一个简单而有效的机制,用于结构化的声音操纵使用声学PB metasurfaces和q-plates.
- 这些发现对声通信,成像和芯片设备的进步具有重大前景.
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