Broadband Ground-Plane Cloak
Broadband Ground-Plane Cloak
复制标题
宽带地平面斗篷
DOI：
10.1126/science.1166949
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发表时间：
2009-01-16
期刊：
影响因子：
56.9
通讯作者：
Smith, D. R.
中科院分区：
文献类型：
--
作者：
Liu, R.;Ji, C.;Smith, D. R.
用电磁波隐身探测物体的可能性最近已成为一个相当感兴趣的话题。斗篷的设计使用变换光学，将保角坐标变换应用于麦克斯韦方程，以获得定义斗篷的一组空间分布的本构参数。在这里，我们提出了一种隐形设计的实验实现，该隐形设计可以隐藏在平面导电平面上的微扰，在该平面下可以隐藏对象。为了匹配所需本构参数的复杂空间分布，我们构建了一个由数千个元素组成的超材料，每个元素的几何形状由自动化设计过程确定。通过使用非共振超材料元件，可以实现地平面隐身，使得该结构具有较宽的工作带宽(在我们的实验中覆盖13-16千兆赫的范围)，并且表现出极低的损耗。我们的实验结果表明，这种类型的斗篷应该可以很好地扩展到光学波长。
The possibility of cloaking an object from detection by electromagnetic waves has recently become a topic of considerable interest. The design of a cloak uses transformation optics, in which a conformal coordinate transformation is applied to Maxwell's equations to obtain a spatially distributed set of constitutive parameters that define the cloak. Here, we present an experimental realization of a cloak design that conceals a perturbation on a flat conducting plane, under which an object can be hidden. To match the complex spatial distribution of the required constitutive parameters, we constructed a metamaterial consisting of thousands of elements, the geometry of each element determined by an automated design process. The ground-plane cloak can be realized with the use of nonresonant metamaterial elements, resulting in a structure having a broad operational bandwidth (covering the range of 13 to 16 gigahertz in our experiment) and exhibiting extremely low loss. Our experimental results indicate that this type of cloak should scale well toward optical wavelengths.