Lithium niobate single crystal fiber with parabolic refractive index cladding

Lithium niobate single crystal fiber with parabolic refractive index profile cladding was achieved by using Mg-ion in diffusion process. It has been proved by experiments that the refractive index profile varies with the diffusion parameters such as the diffusion temperature, diffusion time and the thickness of MgO film. Suitable diffusion temperature is 1050-1100 °C. Mg-ion concentration profiles of the magnesium diffused layer by theoretical simulation are close to the experimental results.