Fig. 1From: High-Performance All-Optical Terahertz Modulator Based on Graphene/TiO2/Si Trilayer HeterojunctionsExperimental design and Raman spectra of graphene. a Schematic of the all-optical THz modulator. The modulator is composed of a single-layer graphene on a p-Si substrate with TiO2 film. b Raman spectra of the graphene on the Si and TiO2/p-Si substratesBack to article page