中国物理B ›› 2021, Vol. 30 ›› Issue (1): 14207-.doi: 10.1088/1674-1056/abb65c

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  • 收稿日期:2020-06-01 修回日期:2020-08-12 接受日期:2020-09-09 出版日期:2020-12-17 发布日期:2020-12-30

Plasmonic characteristics of suspended graphene-coated wedge porous silicon nanowires with Ag partition

Xu Wang(王旭)1, Jue Wang(王珏)1, Tao Ma(马涛)1,2,†, Heng Liu(刘恒)1,3, and Fang Wang(王芳)1,2   

  1. 1 College of Electronic and Electrical Engineering, Henan Normal University, Xinxiang 453007, China; 2 Henan Key Laboratory of Optoelectronic Sensing Integrated Application, Xinxiang 453007, China; 3 Academician Workstation of Electromagnetic Wave Engineering of Henan Province, Xinxiang 453007, China
  • Received:2020-06-01 Revised:2020-08-12 Accepted:2020-09-09 Online:2020-12-17 Published:2020-12-30
  • Contact: Corresponding author. E-mail: matao@htu.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant No. 61627818), the Key Project of Henan Provincial Education Department, China (Grant No. 19A510002), the Natural Science Project of the Cultivation Foundation of Henan Provincial Normal University, China (Grant No. 2017PL04), and the Ph. D. Program of Henan Normal University, China (Grant Nos. 5101239170010 and gd17167).

Abstract: We investigate a graphene-coated nanowire waveguide (GCNW) composed of two suspended wedge porous silicon nanowires and a thin Ag partition. The plasmonic characteristics of the proposed structure in terahertz (THz) frequency band are simulated by the finite element method (FEM). The parameters including the gap between the nanowires and Ag partition, the height of the nanowire, the thickness of the Ag partition, and the Fermi level of graphene, are optimized. The simulation results show that a normalized mode field area of ∼ 10 -4 and a figure of merit of ∼ 100 can be achieved. Compared with the cylindrical GCNW and isolated GCNW, the proposed wedge GCNW has good electric field enhancement. A waveguide sensitivity of 32.28 is obtained, which indicates the prospects of application in refractive index (RI) sensing in THz frequency band. Due to the adjustable plasmonic characteristics by changing the Fermi level (E F), the proposed structure has promising applications in the electro-optic modulations, optical interconnects, and optical switches.

Key words: surface plasmon polariton, graphene, porous silicon, finite element method (FEM)

中图分类号:  (Optical waveguides and couplers)

  • 42.79.Gn
42.82.Et (Waveguides, couplers, and arrays)