Investigation of wavelength conversion by coherent anti-Stokes Raman scattering (CARS) in chalcogenide waveguides

We theoretically propose and demonstrate that chalcogenide waveguide is a more energy efficient platform for Raman-assisted wavelength conversion than silicon waveguide. In spite of its smaller Raman gain, ultra-high Stokes to anti-Stokes conversion efficiency of 5.5dB is observed for chalcogenide waveguide Raman wavelength converter, 10dB higher than its silicon counterpart. Linear phase match can be achieved in chalcogenide waveguide Raman wavelength converter by compensating the large normal material dispersion with waveguide dispersion along. However, nonlinear dynamic phase shift can cause significant fluctuation from the perfect phase match condition, resulting in 20dB efficiency reduction. In addition, we explore the influence of waveguide length on conversion efficiency for future device miniaturization.