Quasi-Phase-Matched Cavity-Enhanced Raman Converter Based on a Silicon Nanowire Ring

We propose a silicon ring Raman converter based on a low-loss nanowire ring, in which the spatial variation of the Raman gain for transverse-electric polarization is used to quasi-phase-match the wavelength conversion process. When using the intrinsic silicon-on-insulator platform, this quasi-phase-matching scheme, combined with the low propagation losses, can give rise to conversion efficiencies that exceed 0 dB at modest pump powers, and that are more than 6 dB higher than those of silicon ring Raman converters in which perfect phase-matching is established through dispersion engineering.