Efficient and broadband wavelength conversion in a slot waveguide with the periodic structure altering the...

High-efficiency wavelength conversion based on the quasi-phase-matching technique is proposed and simulated in a silicon slot waveguide. Due to the tight light confinement and high nonlinear material (silicon nanocrystal) filled in the slot region, a large nonlinear coefficient of 4100/(W·m) is achieved. With the waveguide width changing alternately to manage the phase-mismatch, periodical attenuation of the idler power is suppressed even in the presence of severe dispersion. Numerical simulation shows that an efficiency of -12.3  dB at 1850 nm and a 3-dB bandwidth of 484 nm are available for the 1550 nm wavelength pump in a 4 mm long silicon slot waveguide.