论文标题
通过异常的声学散射塑造非接触力
Shaping contactless forces through anomalous acoustic scattering
论文作者
论文摘要
波浪会赋予动力，并在其路径中施加力。波动动量的转移是非接触式操纵的基本机制，但是常规散射的规则本质地限制了基于操纵物体的形状和大小的辐射力。在这里，我们表明，对于具有亚波长度结构的元图的声波，可以克服这种固有的极限，在该声波中，该力可以通过表面特征的排列来控制，而与对象的整体形状和大小无关。利用这种异常的跨表面散射，我们展示了复杂的致动现象：自我施加，其中跨表面对象由声波自主引导，而无接触式拉力则在其中跨表情对象被波浪拉动。我们的结果表明，将元表面物理学及其全部工具武器库带到机械操作的领域，为各种驱动机制打开了大门，这些机制超出了传统波浪交互的限制。
Waves impart momentum and exert force on obstacles in their path. The transfer of wave momentum is a fundamental mechanism for contactless manipulation, yet the rules of conventional scattering intrinsically limit the radiation force based on the shape and the size of the manipulated object. Here, we show that this intrinsic limit can be overcome for acoustic waves with subwavelength-structured metasurfaces, where the force becomes controllable by the arrangement of surface features, independent of the object's overall shape and size. Harnessing such anomalous metasurface scattering, we demonstrate complex actuation phenomena: self-guidance, where a metasurface object is autonomously guided by an acoustic wave, and contactless pulling, where a metasurface object is pulled by the wave. Our results show that bringing metasurface physics, and its full arsenal of tools, to the domain of mechanical manipulation opens the door to diverse actuation mechanisms that are beyond the limits of traditional wave-matter interactions.
