Hashemizad Seyed Reza, Tsitrin Sam, Yadak Polin, He Yingquan, Cuneo Daniel, Williamson Eric Paul, Liner Devin, Man Weining
Department of Physics and Astronomy, San Francisco State University.
Department of Physics and Astronomy, San Francisco State University;
J Vis Exp. 2014 Sep 26(91):51614. doi: 10.3791/51614.
Recently, disordered photonic materials have been suggested as an alternative to periodic crystals for the formation of a complete photonic bandgap (PBG). In this article we will describe the methods for constructing and characterizing macroscopic disordered photonic structures using microwaves. The microwave regime offers the most convenient experimental sample size to build and test PBG media. Easily manipulated dielectric lattice components extend flexibility in building various 2D structures on top of pre-printed plastic templates. Once built, the structures could be quickly modified with point and line defects to make freeform waveguides and filters. Testing is done using a widely available Vector Network Analyzer and pairs of microwave horn antennas. Due to the scale invariance property of electromagnetic fields, the results we obtained in the microwave region can be directly applied to infrared and optical regions. Our approach is simple but delivers exciting new insight into the nature of light and disordered matter interaction. Our representative results include the first experimental demonstration of the existence of a complete and isotropic PBG in a two-dimensional (2D) hyperuniform disordered dielectric structure. Additionally we demonstrate experimentally the ability of this novel photonic structure to guide electromagnetic waves (EM) through freeform waveguides of arbitrary shape.
最近,无序光子材料已被提议作为周期性晶体的替代物,用于形成完整的光子带隙(PBG)。在本文中,我们将描述使用微波构建和表征宏观无序光子结构的方法。微波波段为构建和测试光子带隙介质提供了最方便的实验样品尺寸。易于操作的介电晶格组件在预印塑料模板上构建各种二维结构时提供了更大的灵活性。一旦构建完成,这些结构可以通过点缺陷和线缺陷快速修改,以制作自由形式的波导和滤波器。测试使用广泛可用的矢量网络分析仪和一对微波喇叭天线进行。由于电磁场的尺度不变性,我们在微波区域获得的结果可以直接应用于红外和光学区域。我们的方法简单,但为光与无序物质相互作用的本质提供了令人兴奋的新见解。我们的代表性成果包括首次通过实验证明在二维(2D)超均匀无序介电结构中存在完整的各向同性光子带隙。此外,我们还通过实验证明了这种新型光子结构能够通过任意形状的自由形式波导引导电磁波(EM)。