  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.
