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研究生:黃建斯
研究生(外文):Chien-Szu Huang
論文名稱:向列型液晶摻雜碳奈管的暫態電流
論文名稱(外文):Transient Current in Nematic Liquid Crystals Doped with Carbon Nanotubes
指導教授:李偉李偉引用關係
指導教授(外文):Wei Lee
學位類別:碩士
校院名稱:中原大學
系所名稱:應用物理研究所
學門:自然科學學門
學類:物理學類
論文種類:學術論文
論文出版年:2005
畢業學年度:93
語文別:中文
論文頁數:66
中文關鍵詞:液晶碳奈管
外文關鍵詞:liquid crystalcarbon nanotubes
相關次數:
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  • 下載下載:25
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本論文研究水平排列向列型液晶摻雜碳奈管及碳60的暫態電流。在純液晶以及摻有雜質的樣品中,研究發現暫態峰值電流出現的時間會隨著外加電壓的增加而縮短。實驗結果也顯示摻雜碳奈管的樣品有較低的臨界電壓,即摻雜碳奈管之樣品在較低外加電壓作用下便會有峰值電流的產生,表示該樣品中的離子電荷在配向層兩側累積最少,使得液晶分子轉向較快且沿著電場方向做排列;而摻雜碳60之樣品則還要在較高外加電壓時才能觀察到峰值電流,代表該樣品有更多的離子電荷在兩側配向層界面累積,因此不利於
Transient currents generated by a switch-on dc voltage in planar cells of pure nematic liquid crystal and of nematic doped with carbon nanotubes or with buckminsterfullerene have been studied. For both doped and undoped cells, the time of occurrence of the peak current decreases with increasing applied voltage. For a nanotube-doped cell, the peak current can be observed even as the applied voltage is in the low-voltage regime. The experimental results show that doping with carbon nanotubes in a cell decreases the ion-charge concentration and, in turn, the critical voltage, allowing the reorientation of the director of the liquid-crystal molecules to take place under a lower applied electric field. In contrast for a fullerence-doped cell, the peak current can only be observed at higher applied voltage, indicating that more ionic charge is adsorbed on the alignment layers, which hinders the nematic director orientation.
中文摘要 i
英文摘要 ii
致謝 iii
表索引 vii
圖索引 viii
第一章 緒論 1
第二章 實驗理論機制 6
2.1 液晶的物性 6
2.1.1 複折射性 6
2.1.2 介電異方性 6
2.1.3 閾値電壓 7
2.2 暫態電流 8
第三章 樣品製作與實驗裝置 11
3.1 樣品製備 11
3.1.1 製作玻璃空盒 11
3.1.2 液晶材料混合及注入 12
3.2 實驗裝置及步驟 13
第四章 結果與分析 15
4.1 厚度為5.7 �慆之液晶樣品在電場作用下的暗電流 15
4.2 厚度為5.7 �慆之液晶樣品在電場作用下的暗電流 20
第五章 結論與未來展望 25
5.1 結論 25
5.2 未來展望 26
參考文獻 27
表格 31

表3.1 配向劑相關參數 31
表3.2 E7液晶分子特性表 32
表3.3 E7液晶之組成 33
表3.4 碳奈管特性表 34
表3.5 碳60特性表 35
表4.1 表4.1 三種5.7 �慆樣品的峰值電流與峰值時間。
(電流單位為nA/cm2;時間單位為ms) 36
表4.2 表4.2 三種25 �慆樣品的峰值電流與峰值時間。
(電流單位為nA/cm2;時間單位為ms) 37

圖3.1 5.7 �慆的液晶玻璃空盒 38
圖3.2 玻璃空盒結構示意圖 39
圖3.3 加入25 �慆厚的墊片,圖中央兩側灰色長條物即為墊片 40
圖3.4 量測暫態電流裝置圖 41
圖4.1 外加偏壓0.5�{10V,純液晶(樣品A)的暫態電流變化情形 42
圖4.2 外加偏壓0.5�{10V,純液晶摻雜碳60(樣品B)的暫態電流變化情形 43
圖4.3 外加偏壓0.5�{10V,純液晶摻雜碳奈管(樣品C)的暫態電流變化情形 44
圖4.4 外加偏壓10V,三種液晶樣品的暫態電流變化情形 45
圖4.5 三種液晶樣品之峰值電流與外加電壓關係圖 46
圖4.6 三種液晶樣品之峰值時間與外加電壓的關係圖 47
圖4.7 三種液晶樣品之總電荷密度與外加電壓的關係圖 48
圖4.8 三種液晶樣品之載子遷移率與外加電壓和峰值時間乘積倒數的關係圖 49
圖4.9 外加偏壓0.5�{10V,純液晶(樣品A)的暫態電流變化情形 50
圖4.9 外加偏壓0.5�{10V,純液晶摻雜碳60(樣品B)的暫態電流變化情形 51
圖4.10 外加偏壓0.5�{10V,純液晶摻雜碳奈管(樣品C)的暫態電流變化情形 52
圖4.11 三種液晶樣品之峰值電流與外加電壓關係圖 53
圖4.12 三種液晶樣品之峰值時間與外加電壓的關係圖 54
圖4.13 三種液晶樣品之總電荷密度與外加電壓的關係圖 55
圖4.14 三種液晶樣品之載子遷移率與外加電壓和峰值時間乘積倒數的關係圖 56
[1]B. Bahadur, Liquid Crystals: Application and Uses (World Scientific, Singapore, 1990).
[2]松本正一、角田市良,《液晶的基礎與應用》,劉瑞祥譯,國立編譯館,民85年。
[3]P. J. Collings and M. Hird, Introduction to Liquid Crystals Chemistry and Physics (Taylor & Francis, London, 1997).
[4]P. G. de Gennes and J. Prost, The Physics of Liquid Crystals, 2nd ed. (Oxford University Press, Oxford, 1993).
[5]N. Sasaki, “Simulation of the voltage holding ratio in liquid crystal displays with a constant charge model,” Japanese Journal of Applied Physics 37, 6065–6070 (1998).
[6]T. Nakanishi, T. Takahashi, H. Mada, and S. Saito, “Transient behavior of voltage holding ratio in nematic liquid crystal cells,” Japanese Journal of Applied Physics 41, 3752–3757 (2002).
[7]H. Mada and K. Osajima, “Time response of a nematic liquid-crystal cell in a switched dc electric field,” Journal of Applied Physics 60, 3111–3113 (1986).
[8]A. Sugimura, Y. Takahashi, H. Sonomura, H. Naito, and M. Okuda, “Transient current dependent on nematic director orientation,” Molecular Crystals and Liquid Crystals 180B, 313–328 (1990).
[9]A. Sugimura, N. Matsui, Y. Takahashi, H. Sonomura, H. Naito, and M. Okuda, “Transient currents in nematic liquid crystals,” Physics Review B 43, 8272–8276 (1991).
[10]H. Naito, K. Yoshida, M. Okuda, and A. Sugimura, “Transient charging current in nematic liquid crystals,” Journal of Applied Physics 73(3), 1119–1125 (1993).
[11]A. Mochizuki, T. Yoshihara, K. Motoyoshi, and S. Kobayashi, “An electric bilayer model of the transient current in a nematic liquid crystal cell,” Japanese Journal of Applied Physics 29, 322–325 (1990).
[12]S. Murakami and H. Naito, “Charge injection and generation in nematic liquid crystal cells,” Japanese Journal of Applied Physics 36, 773–776 (1997).
[13]A. Hassanien, M. Tokumoto, S. Ohshiam, Y. Kuriki, F. Ikazaki, K. Uchida, and M. Yumura, “Geometrical structure and electronic properties of atomically resolved multiwall carbon nanotubes,” Applied Physics Letters 75, 2755–2757 (1999).
[14]Y. Wang and L.-T. Cheng, “Nonlinear optical properties of fullerenes and charge-transfer complexes of fullerenes,” Journal of Physics Chemistry, 96, 1530–1532 (1992).
[15]M. M. Mikhailova, M. M. Kosyreva, and N. V. Kamanina, “On the increase in the charge carrier mobility in fullerene-containing conjugated organic systems,” Technical Physics Letters 28, 450–453 (2002).
[16]E. Hendrickx, B. Kippelen, S. Thayumanavan, S. R. Marder, A. Persoons, and N. Peyghambarian, “High photogeneration efficiency of charge-transfer complexes formed between low ionization potential arylamines and C60,” Journal of Chemical Physics 112, 9557–9561 (2000).
[17]I. C. Khoo, P. H. Chen, M. Y. Shih, A. Shishido, and S. Slussarenko, “Supra optical nonlinearities of methyl-red and azobenzene liquid crystal-doped nematic liquid crystals,” Molecular Crystals and Liquid Crystals 358, 1–13 (2001).
[18]G. Cipparrone, A. Mazzulla, P. Paglisi, F. Simoni, and A. V. Sukhov, “Investigation of photorefractive effect in dye doped PDLC: TBC experiments and photoinduced current measurements,” Molecular Crystals and Liquid Crystals 359, 119–129 (2001).
[19]G. Cipparrone, A. Mazzulla, P. Paglisi, A. V. Sukhov, and R. F. Sukhov, “Transient photoinduced current in dye-doped polymer-dispered liquid crystal,” Journal of the Optical Society of America B 18, 182–186(2001).
[20]W. Lee and C.-S. Chiu, “Observation of self-diffraction by gratings in nematic liquid crystals doped with carbon nanotubes,” Optics Letters 26(8), 521–523 (2001).
[21]W. Lee and S.-L. Yeh, “Optical amplification in nematics doped with carbon nanotubes,” Applied Physics Letters 79(27), 4488–4490 (2001).
[22]W. Lee and H.-C. Chen, “Diffraction efficiency of a holographic grating in a liquid-crystal cell composed of asymmetrically patterned electrodes,” Nanotechnology 14(2), 987–990 (2003).
[23]W. Lee and Y.-L. Wang, “Evidence for holographic image storage in a fullerene-doped liquid-crystal film,” Chinese Journal of Physics 39(4), L295–298 (2001).
[24]W. Lee and Y.-L. Wang, “Voltage-dependent orientational photorefractivity in a planar C60-doped nematic film,” Journal of Physics D: Applied Physics 35(9), 850–853 (2002).
[25]W. Lee, C.-Y. Wang, and Y.-C. Shih, “Effects of carbon nanosolids on the electro-optical properties of a twisted nematic liquid-crystal host,” Applied Physics Letters 85(4), 513–515 (2004).
[26]J. Cognard, “Alignment of nematic liquid crystal and their mixtures,” Molecular Crystals and Liquid Crystals A5, 1–77 (1982).
[27]M. Imai, H. Naito, M. Okuda, and A. Sugimura, “Method for determination of rotational viscosity in nematic liquid crystals,” Japanese Journal of Applied Physics 33, 119–121 (1994).
[28]M. Imai, H. Naito, M. Okuda, and A. Sugimura, “Determination of rotational viscosity of nematic liquid crystals from transient current: numerical analysis and experiment,” Japanese Journal of Applied Physics 33, 3482–3487 (1994).
[29]Y. Iwata, H. Naito, M. Inoue, and H. Ichinose, “Transient current of nematic liquid crystals with negative dielectric anisotropy induced by step-voltage excitation,” Japanese Journal of Applied Physics 12B, 1588–1591 (2004).
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