两步离子交换低损耗光波导功分器的研制

Two-Step Ion-Exchanged Waveguides Splitter with Low-Loss

报道了在热扩散条件下两步离子交换玻璃光波导功分器的理论分析、样品制作和实验测试。为了便于定量分析 ,采用了一种上升反正弦S型分支光波导系统的物理模型 ,得到了在热扩散条件下两步离子交换光功分器波导区的归一化折射率分布和在不同交换时间所形成的玻璃波导折射率分布。在此基础上 ,设计和制作出第一步采用含Tl+ 纯熔盐Tl2 SO4与玻璃含Na+ 进行离子交换形成表面下半圆形波导 ,再把该波导表面脱钛膜放入含Na+ 熔盐NaNO3 中进行第二步离子交换形成掩埋式圆形波导光功分器 ,实现插入损耗为 0 15dB和分光比为 5 0∶5 0的上升反正弦S型玻璃光波导功分器。

A detailed experiment and a theoretical analysis of two-step ion-exchanged glass optical power splitter are reported. In order to facilitate quantitative analysis, a rational model of physics for a rise inverse sine structure of 1×2 S-branch power splitter in glass is proposed. In thermal ion exchange, the distribution of normalized refractive index of two-step ion-exchanged optical power splitter and the distribution of splitter refractive index of different exchange time have been gotten. On this basis, these surface half-round channel waveguides are fabricated by first performing a thermal Tl+ exchange in melt Tl 2SO 4 through a mask patterned on the glass surface. The resulting surface channel waveguides are then buried by second thermal Na+ exchange, unmasked ion exchange, in melt NaNO 3. In this step the Tl+ ions migrate from the glass, and the wavguides are buried below the glass surface. A optical power splitter of insertion loss 0.15 dB and coupling ratio 50∶50 has been realized.