在弹性束中实验实现时间折射和反射
Shaoyun Wang1, Nan Shao1, Hui Chen2
1Department of Mechanical and Aerospace Engineering, University of Missouri, Columbia, MO, USA.
Nature communications
|October 29, 2025
概括
这项研究证明了机械元束中的时间波散射,显示了曲波的受控反射和折射. 这些发现为时力学超材料和音声应用提供了新的可能性.
科学领域:
- 物理 物理学 物理
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
背景情况:
- 在空间接口的波散射遵循常规的保存规律.
- 时间界面引入了独特的波动动态,与空间界面不同.
- 机械超材料为波浪操纵提供可调节的特性.
研究的目的:
- 通过实验证明曲波在时间边界上的折射和反射.
- 探索时间散射现象在音声应用中的潜力.
- 为了能够精确控制波幅和频率,使用时间变化的机械系统.
主要方法:
- 使用带有时间变化的压电补丁的弹性束来改变有效的弹性特性.
- 实现时间界面的时间斯内尔定律和弗雷内尔方程.
- 采用多阶段时间接口和波阻抗的平滑时间变化.
主要成果:
- 在单个时间接口上观察频率转换和相.
- 证明了曲波的振幅和频率光谱的操纵.
- 通过使用时间元束实现波形变形和信息编码.
结论:
- 机械系统中的时间散射提供了新的波浪控制能力.
- 基于这些原则,可以设计时间机械超材料和时间音声晶体.
- 通过临时调制的机械系统,可以精确控制波幅和频率.
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