关键词: 折射率分布, 离子交换光波导, Cs^＋－Na^＋离子交换, 离子交换机理

Abstract: Thc CsNa⁺ ion exchahgc glass waveguides were made by both thermal diffusion and electrical fieldassista1lt diffusion methods. After the investigation of the temperature depcndence of the waveguides, it wasfound that these waveguides exhibit very high thermal stability below the glass transition temperature. Theion cxchangc mechanism of Cs⁺ -Na⁺ ion exchange was found to be non-Fick Diffusion. The stress gradientcanscd by the hugc dimension difference for Cs⁺ and Na⁺ ions, as the electroneutrality field gradient produced due to the large difference in diffusion coefficients between Cs⁺ and Na⁺ ions predominate the diffusion process in ion exchange. The refractive index profiles and concentration profiles obtained by SEM and X-ray energy dispersive analysis can be sell explained by the proposed ion-exchange mechanism.

Key words: ion exchange waveguides, Cs~+-Na~+ ion exchange, refractive index-profile, ion exchange mechansim