Gallium In-Diffusion for the Fabrication of Lithium Niobate Optical Waveguides

Gallium oxide used as a diffusion source for the fabrication of lithium niobate optical waveguides is presented. The optical waveguide properties are investigated and the behavior of the in-diffused gallium is characterized by the secondary ion mass spectroscopy. Single-mode single-polarization optical waveguides with low propagation loss at 632.8 and 1550 nm can be obtained. For reference, the diffusion constant and activation energy of the in-diffused gallium atoms are also obtained.