Nanobiophotonic Center, National Photoelectric Technology, Functional Materials and Application of Science and Technology International Cooperation Center, Northwest University, Xi'an 710069, China.
Phys Chem Chem Phys. 2013 Apr 14;15(14):5084-90. doi: 10.1039/c3cp43994a.
Terahertz (THz) technology has been a promising tool for sensing, spectroscopy, imaging, and communication. However, only few devices have shown efficient performance for future THz technology. Herein, we propose a device based on tunable magnetoplasmons in gated monolayer graphene for THz wave modulation and isolation. The relative transmission and the Faraday rotation angle of the device have been calculated by combining the Fresnel method with the voltage-dependent Drude model. Our results suggest that a superior modulation depth and giant Faraday rotation due to the cyclotron effect in the classical regime by intraband transitions in graphene offer an effective, uniform, and flexible tunability for THz wave. And the modulating and isolating manipulations by graphene can range from 0 to 2 THz, with electron-hole asymmetry originating from variable scattering rate of magnetoplasmons. Moreover, the thickness effect of the thin substrate is also studied for better performance of the device, taking advantage of the unavoidable Fabry-Perot (F-P) effect. This work demonstrates a pathway for efficient THz modulator and isolator based on the magneto-optical polarization effect in graphene.
太赫兹（THz）技术在传感、光谱学、成像和通信方面具有广阔的应用前景。然而，仅有少数器件在未来的太赫兹技术中表现出了高效的性能。在此，我们提出了一种基于门控单层石墨烯中可调谐磁等离子体的器件，用于太赫兹波的调制和隔离。通过将菲涅尔方法与电压相关的 Drude 模型相结合，我们计算了器件的相对透射率和法拉第旋转角。研究结果表明，由于石墨烯中的带内跃迁导致的回旋效应，该器件具有优越的调制深度和巨大的法拉第旋转，为太赫兹波提供了有效的、均匀的和灵活的可调谐性。石墨烯的调制和隔离操作可以在 0 到 2 THz 的范围内进行，这源于磁等离子体的可变散射率引起的电子-空穴不对称性。此外，还研究了薄基底的厚度效应，以利用不可避免的 Fabry-Perot（F-P）效应来提高器件的性能。这项工作展示了一种基于石墨烯中磁光极化效应的高效太赫兹调制器和隔离器的途径。
