Ridge waveguides in lithium niobate as an integration platform for efficient laser and nonlinear optics applications

在本项目中，我们将开发通过高精度切割LiNbO 3制造的不同类型脊形波导的技术和科学基础。我们描述了新的方法，承诺明确的优势，例如，非线性效应和有源器件，如集成激光器的效率。我们将探讨减少高温下表面张力引起的波导损耗的新概念，以及使用导电涂层薄膜抑制光折变损伤的可能性。由于这些是需要某些应用程序，我们将研究不同的方法来实现表面光栅的顶部切割脊与亚微米光栅周期。通过对优化的脊波导进行电场辅助周期极化，可以研制出高效率的准相位匹配非线性波长转换和倍频器件。我们将研究Er和Tm掺杂的LiNbO 3脊形波导，并将展示具有高效率和低泵浦阈值的法布里-珀罗和DBR激光器。最后，我们将展示一个先进的纠缠光子对源与高集成度使用掺铒脊波导激光器和级联的X（2）过程频率转换器。

In this project, we will develop technical and scientific fundamentals of different types of ridge waveguides fabricated by high-precision dicing of LiNbO3. We describe new methods that promise clear advantages in term of e.g. efficiency of nonlinear effects and active devices like integrated lasers. We will explore new concepts for the reduction of waveguide losses by surface tension at high temperatures and possible suppression of photorefractive damage using thin films of conductive coatings. As these are required for certain applications, we will investigate different methods for the realization of surface gratings on top of diced ridges with sub-micron grating periods. By performing electric-field assisted periodic poling of optimized ridge waveguides, high-efficiency QPM nonlinear wavelength conversion and SHG devices will be developed. We will study Er and Tm doped LiNbO3 ridge waveguides and will demonstrate both Fabry-Perot and DBR lasers with high efficiency and low pump thresholds. Finally, we will demonstrate an advanced entangled photon-pair source with high degree of integration using an Er-doped ridge waveguide laser and a cascaded X(2)-process frequency converter.