Hybrid Thin-Film Lithium Niobate/Silicon Waveguide Scheme for Efficient Terahertz Generation

We propose and investigate a hybrid lithium niobate/silicon waveguide scheme to realize an efficient, room-temperature and continuous-wave THz source via difference-frequency generation. The multi-layer structure allows low-loss and strong waveguide confinements at both optical and THz frequencies, and could yield continuous-wave THz generation efficiencies as high as 2.1x10 ⁻² W ⁻¹ at 3 THz. The proposed THz source could become a compact and cost-effective solution for future spectroscopy, communications and remote sensing systems.