当前位置：
X-MOL 学术
›
Phys. Rev. Lett.
›
论文详情
Our official English website, www.x-mol.net, welcomes your
feedback! (Note: you will need to create a separate account there.)
Independent Flexural Wave Frequency Conversion by a Linear Active Metalayer
Physical Review Letters ( IF 8.1 ) Pub Date : 2022-06-16 , DOI: 10.1103/physrevlett.128.244301 Qian Wu 1 , Xiaodong Zhang 2 , P Shivashankar 1 , Yangyang Chen 3 , Guoliang Huang 1
Physical Review Letters ( IF 8.1 ) Pub Date : 2022-06-16 , DOI: 10.1103/physrevlett.128.244301 Qian Wu 1 , Xiaodong Zhang 2 , P Shivashankar 1 , Yangyang Chen 3 , Guoliang Huang 1
Affiliation
|
Wave frequency is a critical parameter for applications ranging from structural health monitoring, noise control, and medical imaging to quantum of energy in matter. Frequency conversion is an inevitable wave phenomenon in nonlinear or time-modulated media. However, frequency conversion in linear media holds the promise of breaking limits imposed by the physics laws of wave diffraction such as Snell’s law and Rayleigh criterion. In this Letter, we physically introduce a linear active metalayer in a structural beam that can convert the wave frequency of an flexural incidence into arbitrary frequencies of transmitted waves, which is underpinned by time modulation of sensing signals and insensitive to incident amplitude. The active element, involving piezoelectric components and time-modulated transfer function, breaks energy conservation such that the generated harmonics can be fully decoupled, making the frequency conversion linear and independent. By leveraging the time-modulated unit, phase-gradient and frequency-gradient metalayers are proposed for frequency-converted wave steering and dynamic beam steering, respectively. The linear active metalayer proposed herein suggests a promising solution to fully control time-domain signals of flexural waves, in stark contrast with existing elastic metasurfaces, regardless of being passive or active.
中文翻译：
线性有源元层的独立弯曲波频率转换
波频率是从结构健康监测、噪声控制和医学成像到物质能量量子等应用的关键参数。频率转换是非线性或时间调制介质中不可避免的波动现象。然而，线性介质中的频率转换有望打破波衍射的物理定律（如 Snell 定律和瑞利准则）所施加的限制。在这封信中，我们在结构梁中物理地引入了一个线性活性元层，它可以将弯曲入射的波频率转换为发射波的任意频率，这以传感信号的时间调制为基础，并且对入射幅度不敏感。有源元件，涉及压电元件和时间调制传递函数，打破能量守恒，使产生的谐波可以完全解耦，使频率转换线性且独立。通过利用时间调制单元，分别提出了相位梯度和频率梯度元层用于频率转换波转向和动态光束转向。本文提出的线性有源超表面提出了一种有前途的解决方案，可以完全控制弯曲波的时域信号，与现有的弹性超表面形成鲜明对比，无论是被动还是主动。
更新日期：2022-06-16
中文翻译：
线性有源元层的独立弯曲波频率转换
波频率是从结构健康监测、噪声控制和医学成像到物质能量量子等应用的关键参数。频率转换是非线性或时间调制介质中不可避免的波动现象。然而，线性介质中的频率转换有望打破波衍射的物理定律（如 Snell 定律和瑞利准则）所施加的限制。在这封信中，我们在结构梁中物理地引入了一个线性活性元层，它可以将弯曲入射的波频率转换为发射波的任意频率，这以传感信号的时间调制为基础，并且对入射幅度不敏感。有源元件，涉及压电元件和时间调制传递函数，打破能量守恒，使产生的谐波可以完全解耦，使频率转换线性且独立。通过利用时间调制单元，分别提出了相位梯度和频率梯度元层用于频率转换波转向和动态光束转向。本文提出的线性有源超表面提出了一种有前途的解决方案，可以完全控制弯曲波的时域信号，与现有的弹性超表面形成鲜明对比，无论是被动还是主动。
京公网安备 11010802027423号