We integrate monolayer TMDCs into silicon-on-insulation (SOI) waveguides and dielectric-loaded surface plasmon polariton (DLSPP) waveguides to enhance nonlinear parameters ( \(\gamma\) ) of silicon-based waveguides. By optimizing the waveguide geometry, we have achieved significantly improved \(\gamma\) . In MoSe2-on-SOI and MoSe2-in-DLSPP waveguide with optimized geometry, the maximum \(\gamma\) at the excitonic resonant peak ( \(\lambda\) p) is 5001.87 W−1m−1 and 119111.94 W−1m−1 respectively for each case. Based on this, we designed all-optical TMDCs-on-SOI phase and extinction waveguide modulators, achieving \(\pi\) -phase and 3 dB modulation with millimeter-scale modulation lengths under an optical pump intensity of 1 GW/ \(\textrm{cm}^{2}\) at the optical communication wavelengths of 1310 nm and 1550 nm. At the \(\lambda\) p of MoSe2, a modulation length of only 75 \(\upmu\) m is required for \(\pi\) -phase modulation, while a modulation length of 1.36 mm is sufficient for 3 dB modulation. Our work provides new insights for achieving miniaturized and low-power optical communication and networking applications.
