具有拓保护的弹性波的零方向折射在一个支柱式的音声晶板
Hong-Kang Li1, Rong-Hua Chen2, Shao-Yong Huo1
1College of Mechanical Engineering, University of South China, Hengyang, 421001, People's Republic of China.
The Journal of the Acoustical Society of America
|December 13, 2024
概括
这项研究引入了一种新的方法,用于使用拓语音晶体对弹性波的零方向折射,避免挑战零指数材料. 这一突破为先进的声学和音声设备提供了对波传播的强有力的控制.
科学领域:
- 物理 物理学 物理
- 材料科学 材料科学 材料科学
- 声学 声学 在声学方面
背景情况:
- 零方向折射对于光学,声学和声学中的波浪操纵至关重要.
- 现有的方法依赖于难以实现的零或接近零的物质指数.
- 拓概念为控制波浪现象提供了一种新的方法.
研究的目的:
- 在没有零指数材料的情况下,证明弹性波的零方向折射.
- 为了利用音声晶体中的拓相位过渡来进行波浪控制.
- 在工程结构中探索强大的波传输.
主要方法:
- 一个支柱式音声晶体 (PnC) 板的构造.
- 通过单元细胞几何操纵诱导拓阶段过渡.
- 在拓界面和周围介质之间实现相位匹配.
主要成果:
- 成功实现了弹性波的零方向折射.
- 证明了伪回旋拓保护的运输.
- 证实了该现象对结构缺陷和不同撞击角度的强度.
结论:
- 拓语音晶体提供了一条可行的途径,以实现零方向折射.
- 这种方法绕过了零指数材料的限制.
- 这些发现为设计定向弹性波天线和发射器提供了新的可能性.
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