铁电SBN薄膜电光系数的测量及其在波导中的应用

利用溶胶-凝胶法在MgO(001)衬底上获得C轴择优取向的铁电铌酸锶钡(SBN)薄膜，主要介绍MgO(001)衬底上SBN60薄膜及掺入的K离子与Nb离子摩尔比例为1：3的SBN60薄膜横向电光系数r51的测量，实验测得不掺K的SBN60薄膜r51值为37．6pm／V，掺K的r51值为58．5pm／V。并由此设计一种基于MgO(001)衬底上的马赫一曾德尔型SBN60薄膜波导调制器，计算出在633nm时，掺K比例为1：3的此种波导调制器半波调制电压值为10V，不掺K的半波电压值为16V，结果说明掺入K离子能增加薄膜的横向电光系数并有效的减少波导的半波调制电压。

Measurement of Electrooptic Coefficients in SBN60 Thin Films and Their Applications in Mach-Zehnder Type Waveguide Modulators

High-quality c-axis oriented SBN60 thin films on MgO(001) substrates have been obtained by the sol-gel process, the transverse electrooptic coefficients r51 of the SBN60 without K-doped and K-doped (with the K+/Nb5+ molar ratio of 1/3) SBN60 thin films were measured as 37.6 pm/V and 58.5 pm/V respectively. The transverse coefficient of the SBN60 films was shown to increase with the K ions doping. Mach-Zehnder type waveguide modulators made of SBN60 thin films were designed. Electrooptic modulation has been demonstrated with the half-wave modulation voltage Vπ=16 V for SBN60 and that of Vπ=10 V for the K-doped SBN60 at 633 nm wavelength. The half-wave modulation voltage was demonstrated to be decreased with the K ion doping.