Wavelength-mode hybrid multiplexed wavelength conversion based on inverse-designed aperiodically poled lithium...

Hybrid multiplexing technology has been considered as an effective method to increase the optical communication capacity. An inverse design method is proposed for thin-film aperiodically poled lithium niobate (TFAPLN) waveguides to support all-optical wavelength conversion of wavelength-mode hybrid multiplexed signals. The TFAPLN waveguide structure is optimized using a simulated annealing algorithm with the objective function of maximum difference frequency generation (DFG) efficiency and minimum uniformity. By adjusting the spacing between adjacent target wavelength channels, a 44-nm 1-dB conversion bandwidth is obtained for three modes (TE₀, TE₁, and TE₂) with an average conversion efficiency of -6.2 dB under a 100-mW pump. The conversion uniformity is less than 0.0243.