The Electric Field Assisted Ion Exchange Waveguide

With the development of integrated optics, people have paid more attention to the graded-index optical waveguides formed by ion exchange, diffusion, and other techniques owing to its wide applications in optical amplifier, laser, communication, sensor, power division, and other related areas. K⁺ ion exchange with the help of an electric field attract more and more concern due to the small loss and low cost.In the paper, it is focused on researches and experiments of K⁺ ion exchange with the help of an electric field. Firstly, it introduced the fundamental theories of ion exchange thoroughly, including planar waveguide theories, and the principle resulting in the refractive index change. Then on the base of some essential mathematical methods in analyzing ion exchange waveguide, the theoretical model of the refractive index founded.This report focuses on research into waveguide prepared by K⁺ ion exchange with the electric field assistance, in order to get well transported wave guide. Because the temperature limitation of agglutinate material, in traditional method, chemical mixture with K⁺ was heated up in low temperature and small change of refractive index was gotten. In new method, adopting pure KNO₃, normal glass is exchanged in 350 OC with the electric field assistance and becomes the multimode waveguide whose loss is 0.61dB/cm. By compared K⁺ ion exchange with the electric field assistance with Ag+ ion exchange, it is shown that K⁺ ion exchange with the help of an electric field is the important method to produce small loss, multimode and low cost waveguide.