新穎有機非線性光學材料DAPSH之晶體生長及性質分析

Growth and Characterization of Organic Nonlinear DAPSH Crystals

翁明堃(Ming-Kung Wong)

指導教授 ： 余琬琴

國立臺北科技大學/工程學院/有機高分子研究所/碩士(2008年)

https://doi.org/10.6841/NTUT.2008.00273

摘要

非線性光學材料在光資訊處理及光電元件上扮演著重要的角色，其中的有機材料深具吸引力，因其光電係數、非線性光學特性遠比無機材料優越，有很高的應用價值，但是晶體生長不易是其缺點。
本論文針對Coe et al.於2002年發表之新穎有機非線性光學材料Trans-4’-(Dimethylamino)-N-phenyl-4-stilbazolium Hexafluorophosphate (DAPSH)進行單晶製備之研究， Kurtz powder test的結果顯示DAPSH的二次非線性光學係數，並不亞於另一熱門非線性光學材料DAST，但此新材料的其他相關研究如晶體生長、晶體性質分析等仍相當缺乏。
本論文除針對DAPSH進行晶體生長的研究外，並建立 DAPSH在acetonitrile的溶解度曲線，且以X-ray繞射儀、電子顯微鏡及光譜儀等儀器進一步量測晶體的各項特性，包括單晶的結構、光學特性等。

關鍵字

非線性光學 ； 晶體生長

並列摘要

There has been considerable research interest in organic nonlinear optical（NLO） materials mainly because of their potential for various applications in optoelectronic and photonic devices. Compared to their inorganic counterparts, well-designed organic NLO materials can have much larger optical nonlinearities. A notable example is DAST（4-dimethylamino-N-methyl-4-stilbazolium tosylate）, which has been shown to exhibit a very large second-order nonlinear optical coefficient of about 10 times that of the inorganic standard LiNbO3. However, the reproducible growth of high quality, large DAST crystals remains a challenging task. Through molecular engineering, it is possible to get new materials that possess better optical properties and growth characteristics.
Recently Coe et al. reported a new stilbazolium salt DAPSH （trans-4’- dimethylamino-N-phenyl-4-stilbazolium hexafluorophosphate）, which was shown to possess a very high SHG activity. The Kurtz powder test studies indicated that the new salt has a pronounced SHG coefficient of 470 times that of urea, similar to that of DAST. Because the effective utilization of any NLO crystals for any conceivable application demands high quality crystals, it is required to develop crystal growth process for DAPSH.
In this study, DAPSH crystals were grown from acetonitrile solutions by the temperature lowering technique. The solubility of DAPSH in acetonitrile was determined. The as-grown crystals were subjected to both structural and optical property studies, including x-ray diffraction, UV-visible spectroscopy, and electron microscopy analyses.

並列關鍵字

Nonlinear optical ； crystal growth

參考文獻

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