Broadband and transparent wavelength conversion based on dispersion-flattened double-slot waveguide

The flat and low second-order dispersion of 0∼-13  ps²/km in a double-slot waveguide is optimized for broadband wavelength conversion. Subsequently, a 3 dB conversion bandwidth of about 1200 nm is presented by four-wave mixing based on the above structure in simulation. Attributed to the small phase mismatch caused by low second- and fourth-order dispersion parameter in a large waveband, the 3 dB conversion bandwidth is almost constant at about 1200 nm with the pump wavelength varying from 2200 to 2800 nm. The results indicate that this dispersion-flattened double-slot waveguide is not only an ideal device for broadband wavelength conversion but also can realize the transparency of pump wavelength, which has potential applications in wavelength conversion.