▎ 摘　　要

We demonstrate that by inserting bi-layer graphene inside silicon waveguide, the modulation ability of the overall waveguide can be greatly enhanced. Moreover, the modulation ability of the waveguide remains stable under the variations of the temperature and the wavelength of the incident light. A Mach-Zehnder modulator based on this structure is proposed and the calculated results show that the modulator exhibits an excellent performance in terms of short length arm (7 mu m), low energy consumption (8 fJ/bit) and high extinction ratio (31 dB). Besides, it requires low applied voltage and can be compatible with CMOS technology.