提出了一种基于硅锗(Ge-on-Si,GOS)的新型亚微米光波导,通过调节二阶色散对此波导的结构进行了优化设计,研究了其在波长为3~6 μm间的连续光波长转换性能.数值结果表明,在脊宽2.8 μm、脊高1.6 μm,平板厚度0.48 μm的优化结构下,当泵浦光波长在靠近二阶零色散点的负色散波长区时可以实现高转换效率宽带中红外波长转换,3 dB转换带宽可达到1664 nm,在0.05 GW/cm2的泵浦光功率密度下,最大转换效率可达到-2.479 dB.该波导在中红外波段具有波长转换带宽大、转换效率高的优点,在未来空间光子网络与通信方面具有潜在的应用前景.

A novel sub-micron optical waveguide based on silicon-on-germanium (Ge-on-Si,GOS) was proposed and by adjusting second-order dispersion curves the waveguide structure were optimized and designed .Then this article studied its wavelength conversion properties between 3 μm and 6 μm.The numerical results show that this waveguide can achieve high conversion efficiency in broadband infrared wavelength conversion when the pump light wavelength near the zero dispersion point at negative wavelength region of the second-order dispersion curves at the optimized waveguide structure which the ridge width is 2.8 μm,ridge high is 1.6 μm and slab thickness is 0.48 μm.The 3 dB conversion bandwidth reaches 1664 nm and the maximum conversion efficiency can reach -2.479 dB at the 0.05 GW/cm2 power density of the pump light .This waveguide has potential applications in terms of future photonic networks and communications space due to its large wavelength conversion bandwidth and high conversion efficiency advantages.