【作者】 童朝健；

【导师】 熊兆贤； 周建华；

【作者基本信息】 厦门大学 ， 材料学， 2008， 硕士

【摘要】 极化聚合物材料具有非线性系数高、电容率低、易加工处理、与现有集成工艺相兼容等特点,因而在集成光学特别是光通信器件领域有着广阔的应用前景。而最近新兴的无机/有机杂化材料,由于兼备聚合物的柔韧性、高透光性和无机物的热稳定性等特点,而备受材料界关注。本文的主要工作就是制备两种体系极化聚合物薄膜,包括主客体掺杂型体系和有机/无机杂化型体系,并运用光漂白工艺制备出以杂化型薄膜为芯层的Y型光波导。实验中首先以分散红1（DR1）为生色团,制备基体为PMMA的主客体掺杂型极化聚合物体系。DR1含量为10wt%的聚合物PR-10的T_g只有94℃,而PMMA的T_g为105℃;并以PR-10为例,对主客体掺杂型极化聚合物薄膜的电晕极化工艺进行优化得出较佳的极化条件为:极化电压为4.5kV,极化时间为30min,极化温度为95℃,极化薄膜的取向序参数为0.182,常温下薄膜表现出较快的弛豫速度,60d后取向度仅为初始值的21%;二次谐波产生（SHG）实验结果表明聚合物薄膜的二阶非线性系数d₃₃为1.90×10^-8esu。然后通过溶胶-凝胶（sol-gel）工艺合成以MMA为有机物骨架,以MSMA为偶联剂,以TEOS为无机前体的有机/无机杂化材料PMMA/SiO₂,并且以此为主体,制备出以DR1为客体的杂化体系;n（TEOS）/[n（MMA）+n（MSMA）]=0.6的样品PCR-0.6不仅其玻璃化温度T_g高达165℃,远高于PMMA/DR1材料,而且杂化薄膜显示出明显改进的热稳定性和优异的抗弛豫性能,电晕极化后在常温下保存20d后取向度依旧保持为初始值的91%,并且趋于稳定不再下降。在此基础上,以PMMA/SiO₂为包层、有机/无机杂化型薄膜为芯层,应用光漂白法制备出Y型光波导,对其制备工艺进行探讨和优化,尤其是铝掩模层的制作和光漂白对波导薄膜的影响。运用光纤与波导直接耦合装置对Y形光波导进行性能测试,由功率计测得Y分支的光强比为44:56,光损耗值约为9dB。更多还原

【Abstract】 There were advantages, for nonlinear optical （NLO） poled polymer materials, of large nonlinear optical coefficient, low permittivity, easy processing and monolithic integration. It was thus expected that they played an important role in the field of integrated optics, especially high performance photonic devices, such as high-speed optical switches, tunable filters and broadband optical modulators. In recent years, organic-inorganic hybrid materials have drawn much attention, as involve the advantages of both organic and inorganic phases such as high transmitance, great flexibility and better stability and toughness.In this thesis, two kinds of NLO polymer thin films including ploymer/chromophore guest-host, organic-inorganic hybrid/chromophore were successfully prepared by dip-coating technique, and a Y-type optical waveguide was obtained using hybrid film as core layer with photo-bleaching technique.Azo-dye polymer films of the guest-host system were prepared with disperse red-1 （DR1） as NLO active chromphore and poly （methylm ethacrylate） （PMMA） as polymer matrix. The T_g of poled polymer with 10wt% DR1 （PR-10） was 94℃, while that of PMMA was 105℃. The poling condition was optimized and the optimal orientation order parameter （Φ） of PR-10 was estimated to be 0.182. After 30d at room temperature, theΦvalue of the poled films decreased into about 70%, showing bad relaxation-resistance. NLO coefficient (d₃₃) of 1.90×10^-8esu was reached for the film after corona poling by the SHG measurement.Using the MMA as organic component, TEOS as inorganic component, MSMA as coupling agent, the organic-inorganic hybrid PMMA/SiO₂ was also synthesized successfully via sol-gel route. Hydrid films of PMMA/SiO₂/DR1 were developed. The T_g of hybrid sample PCR-0.6 with n（TEOS）/[n（MMA）+n（MSMA）]=0.6 was 165℃, much higher than that of PR-10. The hybrid films showed excellent stability of chromophore molecules ordered as theΦwas able to be maintained about 91% of its initial value at room temperature for 60d.Meanwhile, a Y-type optical waveguide was obtained using PMMA/SiO₂/DR1 as the core layer and PMMA/SiO₂ as the substrate with photo-bleaching technique, and the preparation parameter was optimized in details, especially the fabricaiton of Al-mask and its effect on properties of films with photo-bleaching. The optical properties of the Y-type optical waveguide were testd with the coupling optical fiber, in which the optical power ratio was 44:56 for two branches and the optical loss was around 9dB with a powermeter.更多还原