Fabrication of serially-grafted optical wave guide of organic functional crystal and polymer

有机晶体光波导是一种很有前途的器件，但由于其光损耗大，需要与透明聚合物波导进行串联接枝。在各种有机晶体中，我们研究了一种有机盐，4-N， n -二甲氨基-4'- n -甲基-甲酰基磺酰腙，DAST，这是一种很有前途的功能晶体。它的最大NLO系数d_<11>为~ 540V，电光（EO）系数r_<11>为~ 55pm/V （λ=1.54μm）。DAST晶体极易溶解于有机溶剂和水中，是制造光波导相对困难的材料。这是非常关键的，因为波导制造方法的选择将受到限制。为此，我们采用特殊的升压法制备了DAST与透明聚合物的串联接枝光波导。基于光刻技术和反应离子刻蚀技术，我们成功地制造出了一种串联接枝结构的波导，这是晶体与聚合物结合波导的第一次。对于NLO有机晶体波导，仅报道了两种通常不溶于水的分子晶体，尽管它们的损耗很大，大于20dB/cm。对于连续接枝5mm长的DAST结构，损耗约为10dB/cm和~ 6dB/cm。采用光漂白法制备了DAST串联接枝波导。我们已经报道了基于光异构和光分解的DAST晶体是可光漂白的。因此，我们选择含偶氮苯的透明聚合物染料作为聚合物波导进行光漂白。在偶氮染料合成新型聚芳醚的基础上，制备了DAST与聚芳醚的串联接枝波导。我们已经成功地用这种简单的光漂白技术制造了它。综上所述，迄今为止我们成功地制备了一种串联接枝的有机功能晶体和透明聚合物。由DAST晶体和聚合物组成的波导有望应用于光通信系统的功能光学电路。少

Organic crystal optical waveguides are promising device for practical photonic applications though because of their large optical loss, they should be serially grafted with transparent polymer waveguides. Among a variety of organic crystals we investigated an organic salt, 4-N, N-dimethylamino-4'-N-methyl-stilbazorium tosylate, DAST, an a promising functional crystal. It is of particular interest because its largest NLO coefficient d_<11> is 〜540V and electro-optic (EO) coefficient r_<11> is 〜55pm/V (λ=1.54μm). DAST crystal is relatively hard to fabricate optical waveguide because it is very easy to dissolve into organic solvents as well as in water. This is very critical because the selection of the waveguide fabrication methods will be limited.So we had used special lift off method to fabricate a serially grafted optical waveguide of DAST and transparent polymer. Based on the photolithography and reactive ion etching technology, we had succeeded to fabricate a serially grafted struct … More ure of the waveguide, for the first time as far as the combined waveguide of crystal and polymer. As far as NLO organic crystal waveguide concerns, only two molecular crystals that are usually insoluble in water were reported, though their loss was large, larger than 20dB/cm. In the case of the DAST, loss was around 10dB/cm and 〜6dB/cm with serially grafted structure of 5 mm long DAST. DAST serially grafted waveguide was also fabricated using photobleaching. We had already reported that the DAST crystal is photo-bleachable based on photo-isomerization and photodecomposition. So as a polymer waveguide, we had selected azobenzene-dye containing transparent polymer to photobleach. After synthesizing novel polyarylether with azo-dye, we have fabricated a serially grafted waveguide of DAST and the polyarylether. We had succeeded to fabricate it using this simple photobleaching technology.In conclusion, a serially grafted organic functional crystal and transparent polymer was successfully fabricated for the time as far as we know. The waveguide of the DAST crystal and polymer is expected to apply for functional optical circ in optical telecommunication system. Less