Cheng Bo Han, Chen Hong Wen, Jen Yi-Jun, Lan Yung-Chiang, Tsai Din Ping
Department of Electro-Optical Engineering, National Taipei University of Technology, Taipei 106, Taiwan.
Department of Photonics and Advanced Optoelectronic Technology Center, National Cheng Kung University, Taiwan 70101, Taiwan.
Sci Rep. 2016 Jun 29;6:28799. doi: 10.1038/srep28799.
Dielectric-graphene-dielectric (DGD) structure has been widely used to construct optical devices at infrared region with features of small footprint and low-energy dissipation. The optical properties of graphene can be manipulated by changing its chemical potential by applying a biased voltage onto graphene. However, the excitation efficiency of surface wave on graphene by end-fire method is very low because of large wavevector mismatch between infrared light and surface wave. In this paper, a dielectric-semiconductor-dielectric (DSD) tapered waveguide with magnetic tunability for efficient excitation of surface waves on DGD at infrared region is proposed and analyzed. Efficient excitation of surface waves on DGD with various chemical potentials in graphene layer and incident frequencies can be attained by merely changing the external magnetic field applied onto the DSD tapered waveguide. The electromagnetic simulations verify the design of the proposed structure. More importantly, the constituent materials used in the proposed structure are available in nature. This work opens the door toward various applications in the field of using surface waves.
介质-石墨烯-介质（DGD）结构已被广泛用于构建红外区域的光学器件，具有占地面积小和能量耗散低的特点。通过在石墨烯上施加偏置电压来改变其化学势，可以操纵石墨烯的光学性质。然而，由于红外光与表面波之间的大波矢失配，端射法对石墨烯表面波的激发效率非常低。本文提出并分析了一种具有磁可调性的介质-半导体-介质（DSD）锥形波导，用于在红外区域高效激发DGD上的表面波。只需改变施加在DSD锥形波导上的外部磁场，就可以在石墨烯层中具有各种化学势和入射频率的情况下高效激发DGD上的表面波。电磁模拟验证了所提出结构的设计。更重要的是，所提出结构中使用的组成材料在自然界中是可用的。这项工作为表面波应用领域的各种应用打开了大门。
