Artificial Dielectrics: Ordinary Metallic Waveguides Mimic Extraordinary Dielectric Media
Artificial Dielectrics: Ordinary Metallic Waveguides Mimic Extraordinary Dielectric Media
复制标题
人造电介质：普通金属波导模仿特殊电介质
DOI：
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发表时间：
2014
影响因子：
3.6
通讯作者：
D. Mittleman
中科院分区：
文献类型：
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作者：
R. Mendis;D. Mittleman
考虑电磁波在两个平行金属板之间的空间中传播。这种情况通常是本科生遇到的导波的第一个例子，因为解决方案（导模）是解析的，很容易获得。然而，这个看似简单的配置可以引起许多有趣的，甚至违反直觉的现象。对于电场指向平行于两块金属板表面的模式集，板之间的区域虽然只是空的空间，但模仿了具有不同于真空中波的波速c的波速yp的电介质的性质。因此，波导可以被描述为具有不同于1的有效折射率n=c/yp的人工电介质[1]。与自然发生的n 2 1相反，n可以具有小于1的值。这些波导为基础的人工微波最早是在大约半个世纪前由微波界在一小部分工作中引入的。如这里所讨论的，当从微波区域移动到太赫兹（THz）区域时产生的波长缩放导致更实用的结构尺寸。这为这些人工晶体在太赫兹科学和技术中的各种新颖和异国情调的应用提供了新的生命。
Consider an electromagnetic wave propagating in the empty space between two parallel metal plates. This situation is often the first example of guided waves encountered by undergraduate students since the solutions (the guided modes) are analytic and easily obtained. And yet, this seemingly simple configuration can give rise to a number of interesting and even counterintuitive phenomena. For the set of modes with the electric field pointing parallel to the surfaces of the two metal plates, the region between the plates, though simply empty space, mimics the properties of a dielectric medium with a wave velocity yp different from c, that of waves in vacuum. The waveguide therefore can be described as an artificial dielectric [1] with an effective refractive index n=c/yp different from unity. In contrast to naturally occurring dielectrics for which n 2 1, n can have a value less than unity. These waveguide-based artificial dielectrics were first introduced in a small body of work by the microwave community about half a century ago. As discussed here, the wavelength scaling that results when moving from the microwave region to the terahertz (THz) region results in more practical structural dimensions. This gives new life to these artificial dielectrics for a variety of novel and exotic applications in THz science and technology.