Advanced Optical TechnologiesPublished 25 July 2023Three-dimensional femtosecond laser inscription of type a-based high-efficiency first-order waveguide Bragg gratingsRomain Laberdesque · Laura Loi · Théo Guérineau · Alain Abou Khalil · Sylvain Danto · Thierry Cardinal · Lionel Canioni · Yannick PetitAdvanced Optical Technologiesdoi 10.3389/aot.2023.1237679