亚波长电磁波隧穿

文章介绍一种具有亚波长隧穿特性的电磁波人工复合材料.这种材料由具有不同特性的层状材料组成一“三明治”多层复合体：即ABA板.其中夹心板B为一完全阻挡电磁波的金属网（具有负介电常数-ε的金属亚波长网格）,而两夹板A可以由具有周期排列的正介电常数（＋ε）或负磁导率（-μ）的单元体构成.当电磁波入射此“三明治”体时,特定频率的电磁波会透过而产生透带.这种具有亚波长隧穿的现象实际上是由夹板上单元体的局域谐振诱导各层间电磁场增强引起的.

Subwavelength tunneling of electromagnetic waves

We describe an electromagnetic(EM) composite material that possesses subwavelength tunneling characteristics.The sample is constructed as a multilayered "sandwich",i.e.,ABA structure.The core plate is a metallic mesh with holes subwavelength in size compared to the incident EM wavelength,while the two outer layers are fabricated with units of periodically arranged positive dielectric permittivity or negative magnetic permeability.Up to 100% transmission of normally incident EM waves has been demonstrated in the microwave regime through such "sandwiches" at certain frequencies,forming so called "passbands".The phenomenon of subwavelength tunneling is caused by the electromagnetic enhancement at and between the interfaces of the different layers,induced by local resonances of the two outer plates.