Numerical analysis and optimization of quasi-phase-matched second-harmonic-generation in LiNbO3 waveguide
准位相匹配铌酸锂波导倍频特性分析与优化设计

Scalar finite-element-method was used to calculate the effective index and mode field distribution in periodically poled LiNbO 3 waveguide, where the relationship of the refractive index of LiNbO 3 and its temperature was concerned. Based on the results, the relationship between quasi-phase-matched second-harmonic-generation (SHG) efficiency and the periodically poled grating period, fundamental wavelength, bulk temperature was analyzed, and the theoretical results fit well with the experiments. Furthermore, the dependences of converted SHG efficiency on the annealed proton exchanged waveguide parameter, the grating period on the crystal temperature, and the bandwidth of temperature and fundamental wavelength on the length of grating period were analyzed and optimized.