Design of germanium-silicon carbide hybrid waveguides for mid-infrared third-order parametric conversion

Abstract

We propose a mid-infrared (MIR) waveguide in which two pure photonic fundamental modes are perfect phase-matched for third harmonic generation (THG) and triple photon generation (TPG). The waveguide is based on the germanium–silicon carbide–germanium (Ge–SiC–Ge) hybrid structure. Leveraging the anomalous dispersion of SiC near the resonance, the THG phase mismatch between two fundamental modes can be overcome. By carefully engineering the nonlinear mode overlap, the MIR THG performance is investigated in detail. In addition, a MIR TPG rate of ∼10−3Hz is estimated. The proposed scheme provides an integrated platform for future MIR all-optical signal processing and quantum signal processing.