Quasi-phase-matched four-wave mixing generation between C-band and mid-infrared regions using a symmetric hybrid plasmonic waveguide grating.

Abstract

A symmetric hybrid plasmonic waveguide (SHPW) configuration based on quasi-phase-matched (QPM) four-wave mixing (FWM) is proposed to realize efficient FWM conversion between the C-band and mid-infrared (mid-IR) regions. Due to the ability to allow strong confinement of light, an extremely large nonlinear parameter γ>104 m-1 W-1 and a very low propagation loss ∼3×10-3 dB/μm accompanying the sub-λ scale (effective mode area Aeff∼3×10-2 μm2) are achieved by optimally designing the SHPW geometrical parameters. In addition, a QPM technique is adopted to achieve a relatively long effective length of FWM nonlinear process by constructing a long SHPW grating, thereby resulting in highly efficient wavelength conversion without rigorous dispersion engineering of waveguide structures. By using numerical simulations we have demonstrated that, for a pump wavelength of 1,800nm, an efficient and flat FWM conversion of ∼-17 dB (∼-22 dB) could be realized around a target signal wavelength of the C-band: 1,530-1,565nm (mid-IR: 2,118-2,180nm), in a 1,000μm-long grating with a serious phase mismatch.