Wavefront modulation and subwavelength diffractive acoustics with an acoustic metasurface
Wavefront modulation and subwavelength diffractive acoustics with an acoustic metasurface
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DOI：
10.1038/ncomms6553
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发表时间：
2014-11-01
影响因子：
16.6
通讯作者：
Cummer, Steven A.
中科院分区：
文献类型：
--
作者：
Xie, Yangbo;Wang, Wenqi;Cummer, Steven A.
亚表面是一类具有平面轮廓和亚波长厚度的新型波前整形器件。具有超低轮廓但具有非凡的波浪操纵特性的声学亚表面将非常适合于提高许多基于声波的应用的性能。然而，与传统的超材料设计方法相比，设计具有与其电磁对应物类似功能的声学超表面仍然具有挑战性。本文介绍了一种基于锥形迷宫超材料的声学超表面的设计与实现。该亚表面不仅可以像广义斯奈尔定律所期望的那样引导声束，而且还表现出从传播波到表面模的转换、特殊的波束操纵和通过高阶衍射的表观负折射等各种独特的性质。这种设计者声学元表面为声信号调制设备提供了一种新的设计方法，并可用于诸如声成像、波束控制、超声透镜设计和基于声表面波的应用。
Metasurfaces are a family of novel wavefront-shaping devices with planar profile and subwavelength thickness. Acoustic metasurfaces with ultralow profile yet extraordinary wave manipulating properties would be highly desirable for improving the performance of many acoustic wave-based applications. However, designing acoustic metasurfaces with similar functionality to their electromagnetic counterparts remains challenging with traditional metamaterial design approaches. Here we present a design and realization of an acoustic metasurface based on tapered labyrinthine metamaterials. The demonstrated metasurface can not only steer an acoustic beam as expected from the generalized Snell's law, but also exhibits various unique properties such as conversion from propagating wave to surface mode, extraordinary beam-steering and apparent negative refraction through higher-order diffraction. Such designer acoustic metasurfaces provide a new design methodology for acoustic signal modulation devices and may be useful for applications such as acoustic imaging, beam steering, ultrasound lens design and acoustic surface wave-based applications.