低阈值极化电压玻璃光波导电光效应的研究

采用热极化技术对掺锗玻璃条形光波导进行极化,通过光纤连接 (单模) 的Mach Zehnder Interferometer 系统测量条形波导内诱导出的电光效应,系统地研究了大气环境下极化条件(极化温度、极化时间、极化电压)对电光效应的影响.结果表明:在最佳极化条件下(406℃、-2.4 kV、20 min),波导内的电光系数为r_TM=0.059±0.001 pm/V, r_TE=0.053±0.001 pm/V,且波导结构中存在一个较低的阈值极化电压(100 V)和阈值极化温度(80℃),此时在波导样品内仍能被激发出可观察的电光效应;实验还发现采用负极化诱导方式产生的电光系数较正极化提高15%左右.

Electro-optic Effect of Glass Waveguides with Lower Threshold of Poling Conditions

Silicon-based channel waveguides are poled by thermal poling. A fiber-based (single mode) Mach-Zehnder interferometer is utilized to measure the linear electro-optic effect. Poling conditions (poling temperature, poling time, poling voltage) are optimized in air environment. The results show that, the electro-optic coefficient is r_TM=0.059±0.001 pm/V, r_TE=0.053±0.001 pm/V at the optimized conditions (-2.4 kV, 406℃, 20 min). At the same time, the waveguide has a lower threshold of poling voltage and poling temperature. An effective electro-optic signal can be observed when poling voltage drops to about 100 V or poling temperature drops to about 80℃. The results also suggest that the electro-optic coefficient increases of 15% at negative poling than positive poling.