Polarization-independent terahertz wave modulator based on graphene-silicon hybrid structure

Du Liang-Liang^{1, 2}, Li Quan², Li Shao-Xian², Hu Fang-Rong¹, Xiong Xian-Ming¹, Li Yan-Feng¹, Zhang Wen-Tao^{1, †,}, Han Jia-Guang^{2, ‡,}

(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.