Design and Optimization of a Graphene Modulator Based on Hybrid Plasmonic Waveguide with Double Low-Index Slots

• Published in: Plasmonics (Norwell, Mass.) Mass.), 2019-02, Vol.14 (1), p.133-138
• Main Authors: Luan, Jinyu, Fan, Meiyong, Zheng, Pengfei, Yang, Huimin, Hu, Guohua, Yun, Binfeng, Cui, Yiping
• Format: Article
• Language: English
• Subjects: Biochemistry; Biological and Medical Physics; Biophysics; Biotechnology; Chemistry; Chemistry and Materials Science; Design optimization; Electric fields; Figure of merit; Graphene; Modulation; Modulators; Nanotechnology; Power consumption; Strong interactions (field theory); Wave propagation; Waveguides
• ISSN: 1557-1955; 1557-1963
• DOI: 10.1007/s11468-018-0785-4

Graphene modulators based on surface plasmonic waveguides enable a strong interaction between light and graphene because great electric field enhancement occurs in the sub-wavelength region. However, a tight field confinement will cause a large metal absorption of light. Thus, graphene modulator base on hybrid plasmonic waveguide has a tradeoff between the propagation loss and the modulation depth. Here, we achieved a good balance between them by designing and optimizing an electro-optic modulator based on hybrid plasmonic waveguide with four graphene layers. The structure of the waveguide is metal/insulator/Si/insulator/metal. The modulation depth and the propagation loss of the modulator are 0.524 and 0.05 dB/μm respectively, which make a relatively high figure of merit about 10.5. Also the obtained modulation bandwidth and power consumption are 150 GHz and 0.607 pJ/bit, respectively.