Wang Lei, Zhang Xintong, Li Lingqi, Lu Qingming, Romero Carolina, Vázquez de Aldana Javier R, Chen Feng
Opt Express. 2019 Feb 4;27(3):2101-2111. doi: 10.1364/OE.27.002101.
We report on the fabrication of depressed cladding waveguides in periodically poled MgO doped LiTaO by using low-repetition-rate femtosecond laser writing, and their use for guided-wave second harmonic generation (SHG). The cladding waveguides exhibit different guiding performance along the extraordinary and ordinary polarizations. The temperature-dependent quasi-phase-matching (QPM) is realized to obtain SHG in the depressed cladding waveguides. The results show that the QPM temperature was dependent on the poling period and on the features of the cladding waveguides. The highest nonlinear conversion efficiency (0.74%Wcm) was found in the waveguide fabricated with large scanning velocity (0.75 mm/s) and small radius (15 μm).
我们报道了通过使用低重复率飞秒激光写入技术在周期性极化掺氧化镁的钽酸锂中制备凹陷包层波导，以及它们在导波二次谐波产生（SHG）中的应用。包层波导在异常极化和正常极化方向上表现出不同的导波性能。实现了温度依赖的准相位匹配（QPM）以在凹陷包层波导中获得SHG。结果表明，QPM温度取决于极化周期和包层波导的特性。在以大扫描速度（0.75毫米/秒）和小半径（15微米）制备的波导中发现了最高的非线性转换效率（0.74%W/cm）。
