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在二氧化气凝元材料中的伪脊柱依赖的声学拓边缘和角状况)
Chen Liu1,2, Wei Xiong1, Wenjie Liu1
1MOE Key Laboratory of Modern Acoustics, Department of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, People's Republic of China.
The Journal of the Acoustical Society of America
|May 23, 2024
概括
研究人员使用气凝设计了一种新的声学拓绝缘体. 这种柔软的超材料能够在亚波长尺度上进行强大的声音操纵,支持高级声学设备的独特边缘和角状态.
科学领域:
- 声学 声学 在声学方面
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
背景情况:
- 拓绝缘器启发了类似的拓声学,用于声音操纵.
- 实现使用软元材料的低波长声学拓绝缘体具有挑战性.
- 现有的方法通常依赖于理想的参数或复杂的人工结构.
研究的目的:
- 设计和演示一个亚波长的声学二级拓绝缘体.
- 为了利用纳米级的多孔固体材料,特别是气凝,作为软的元材料.
- 为了实现同时的伪旋转依赖的拓边缘和角状态.
主要方法:
- 使用纳米级多孔氧气凝作为柔软的声学超材料.
- 通过在空气矩阵中嵌入氧气凝来构建蜂格子.
- 进行模拟和实验验证,以确认材料特性和拓状态.
主要成果:
- 证明了氧化气凝作为亚波长软声学元材料的能力.
- 在蜂巢网格结构中观察到一个双迪拉克.
- 通过超细胞操纵诱导了拓相位过渡,导致带逆转.
- 确认了声波传播的强大的1D边缘状态.
- 发现了 0D 角状态,以有效地限制低波长能量.
结论:
- 气凝有效地作为用于亚波长拓声学的软元材料起作用.
- 拟议的声晶表现出强大的拓边缘和角状态.
- 这些发现为使用现实软材料的实用亚波长拓声学设备铺平了道路.
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