Meta-fences: blocking waves utilizing a layer of identical tiny scatters

TL;DR

This paper introduces a lightweight, flexible meta-fence made of tiny scatters that effectively blocks and guides flexural waves in plates, offering a compact alternative to bulky wave control devices with broad frequency range capabilities.

Contribution

The study presents a novel meta-fence design using identical tiny scatters for omnidirectional wave blocking and routing, surpassing traditional methods in size and flexibility.

Findings

Broadband wave blocking from 3 to 7 kHz demonstrated

Meta-fence can be assembled into arbitrary waveguides

Significant advantages over traditional isolators and waveguides

Abstract

Wave steering by artificial materials (for example, phononic crystals and acoustic metamaterials) is a fascinating frontier in modern physics and engineering, but suffers from bulky sizes and intractable challenges in fabrication. Here, a sparse layer of identical tiny scatters, which we call meta-fences, is presented with a non-destructive way to omnidirectionally block flexural waves in plates. The underlying mechanism is that the restraining force and moment of the scatter are tuned simultaneously to counter-balance the incident wave. Both our experimental results and numerical analysis have demonstrated that broadband wave sources ranging from 3 to 7 kHz can be segregated from the protected area by the meta-fence. In addition, the meta-fence is further assembled into a waveguide routing with an arbitrary configuration. Compared with previous isolators and waveguides, our meta-fences exhibit absolute advantages in compact size, flexible configuration, and high structural strength. The current scenario sheds light on the design of lightweight-and-strong architectures for vibration control and energy harvesting with a high efficiency, and can be extended to microfluidics, acoustics, seismology and other fields.