Polarization-independent terahertz wave modulator based on graphene-silicon hybrid structure
Du Liang-Liang1, 2, Li Quan2, Li Shao-Xian2, Hu Fang-Rong1, Xiong Xian-Ming1, Li Yan-Feng1, Zhang Wen-Tao1, †, , Han Jia-Guang2, ‡,
       

(a) Peak-to-peak values of terahertz time-domain signals transmitted through the sample controlled by the bias under different photoexcitation powers; (b) transmitted terahertz time-domain signals at various gate bias voltages under a photoexcitation power of 400 mW. Inset shows corresponding modulation depths with taking the amplitude transmission at 0 V (T(0 V)) as a reference.