Fano resonances in THz metamaterials composed of continuous metallic wires and split ring resonators
Fano resonances in THz metamaterials composed of continuous metallic wires and split ring resonators
复制标题
DOI：
10.1364/oe.22.026572
复制
发表时间：
2014-11-03
期刊：
影响因子：
3.8
通讯作者：
Ozbay, Ekmel
中科院分区：
文献类型：
--
作者：
Li, Zhaofeng;Cakmakyapan, Semih;Ozbay, Ekmel
我们从理论和实验上证明，Fano共振可以在太赫兹超材料，是由周期性的连续金属线穿着周期性的开口环谐振器。在较窄的频率范围内发现了非对称的Fano线型。采用传输线与集总元件模型相结合的方法，不仅可以拟合由于连续金属线传输连续体与开口环谐振器亮谐振模之间的耦合和干涉而引起的Fano谐振的传输谱，而且还可以揭示开口环谐振器电容变化引起的Fano谐振频移。因此，在Fano结构的设计中，所提出的理论模型比传统的耦合振子模型显示出更多的能力。得到了Fano结构的有效群折射率参数，在Fano共振处得到了大于800的大群折射率，可用于慢光器件。(C)2014年美国光学学会
We demonstrate theoretically and experimentally that Fano resonances can be obtained in terahertz metamaterials that are composed of periodic continuous metallic wires dressed with periodic split ring resonators. An asymmetric Fano lineshape has been found in a narrow frequency range of the transmission curve. By using a transmission line combined with lumped element model, we are able to not only fit the transmission spectra of Fano resonance which is attributed to the coupling and interference between the transmission continuum of continuous metallic wires and the bright resonant mode of split ring resonators, but also reveal the capacitance change of the split ring resonators induced frequency shift of the Fano resonance. Therefore, the proposed theoretical model shows more capabilities than conventional coupled oscillator model in the design of Fano structures. The effective parameters of group refractive index of the Fano structure are retrieved, and a large group index more than 800 is obtained at the Fano resonance, which could be used for slow light devices. (C) 2014 Optical Society of America