Xiao-Ping Ren1, Ren-Hao Fan1,*, Ru-Wen Peng1,*, Xian-Rong Huang2,*, Di-Hu Xu1, Yu Zhou1, and Mu Wang1
- 1National Laboratory of Solid State Microstructures and School of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
- 2Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA
In this work, we demonstrate both theoretically and experimentally that nonperiodic metallic gratings can become transparent for broadband terahertz waves. It is shown that broadband high transmission appears in aperiodic metallic gratings (including quasiperiodic and disordered ones), which originates from the nonresonant excitations in the grating system. Quasiperiodic and disordered metallic gratings effectively weaken and even eliminate Wood's anomalies, which are the diffraction-related characters of periodic gratings. Consequently, both the transparence bandwidth and transmission efficiency are significantly increased due to the structural aperiodicity. An optimal condition is also achieved for broadband high transparency in aperiodic metallic gratings. Experimental measurements at the terahertz regime reasonably agree with both analytical analysis and numerical simulations. Furthermore, we show that for a specific light source, for example, a line source, a corresponding nonperiodic transparent grating can be also designed. We expect that our findings can be applied for transparent conducting panels, perfect white-beam polarizers, antireflective conducting solar cells, and beyond.
DOI: http://dx.doi.org/10.1103/PhysRevB.91.045111
©2015 American Physical Society
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