Transient Reorientation of a Doped Liquid Crystal System under a Short Laser Pulse
-
Abstract
The transient optical nonlinearity of a nematic liquid crystal doped with azo-dye DR19 is examined. The optical reorientation threshold of a 25-μm-thick planar-aligned sample of 5CB using a 50ns pulse duration 532nm YAG laser pulse is observed to decrease from 800mJ/mm2 to 0.6mJ/mm2 after the addition of 1 vol% azo dopant, a reduction of three orders of magnitude. When using a laser pulse duration of 10ns, no such effect is observed. Experimental results indicate that the azo dopant molecules undergo photoisomerization from trans-isomer to cis-isomer under exposure to light, and this conformation change reorients the 5CB molecules via intermolecular coupling between guest and host. This guest-host coupling also affects the azo photoisomerization process. -
References
[1] Durbin S D et al 1981 Phys. Rev. Lett. 47 1411 [2] Hsiung H et al 1984 Phy. Rev. A 30 1453 [3] Hu X D et al 2003 Acta Phys. Sin. 52 192 (inChinese) [4] Janossy I 1994 Phys. Rev. E 49 2957 [5] Gibbons W M et al 1991 Nature 351 49 [6] Chen A G and David J B 1992 Opt. Lett. 17 441 [7] Andy Y G FUH et al 2003 Jpn. J. Appl. Phys. 424406 [8] Lin Z Y et al 2000 Phys. Lett. A 270 326 [9] Xiang Y et al 2008 J. Appl. Phys. 104 063107 [10] Xiang Y et al 2006 Phys. Lett. A 357 159 [11] Khoo I C et al 1993 IEEE J. Quantum Electron. 29 1444 [12] Iacobescu G et al 2008 J. Magn. Magn. Mater. 320 2180 [13] Simoni F et al 1999 J. Phys.: Condens. Matter 11 439 [14] Egami C and Suzuki Y 1997 Appl. Phys. B 64471 [15] Serak S V et al 2002 Liquid Crystals 29 19 [16] Kovalev A et al 2000 Opt. Commun. 183 503 [17] Rodriguez F J et al 2005 J. Chem. Phys. 123204706 -
Related Articles
[1] GUO Xiao-Song, BAO Zhong, ZHANG Shan-Shan, XIE Er-Qing. A Novel Model of the H Radical in Hot-Filament Chemical Vapor Deposition [J]. Chin. Phys. Lett., 2011, 28(2): 028101. doi: 10.1088/0256-307X/28/2/028101 [2] CHEN Peng, SHEN Bo, ZHU Jian-Min, CHEN Zhi-Zhong, ZHOU Yu-Gang, XIE Shi-Yong, ZHANG Rong, HAN Ping, GU Shu-Lin, ZHENG You-Dou, JIANG Shu-Sheng, FENG Duan, Z. C. Huang. Microstructures of GaN Buffer Layers Grown on Si(111) Using Rapic Thermal Process Low-Pressure Metalorganic Chemical Vapor Deposition [J]. Chin. Phys. Lett., 2000, 17(3): 224-226. [3] QI Zhen, HUANG Jing-yun, YE Zhi-zhen, LU Huan-ming, CHEN Wei-hua, ZHAO Bing-hui, WANG Lei. Growth and Characterization of High Quality Sil-x-yGexCy Alloy Grown by Ultra-High Vacuum Chemical Vapor Deposition [J]. Chin. Phys. Lett., 1999, 16(10): 750-752. [4] BAI Yi-zhen, JIANG Zhi-gang, WANG Chun-lei, JIN Zeng-sun, LÜ Xian-yi, ZOU Guang-tian. Effects of Alcohol Addition on the Deposition of Diamond Thick Films by dc Plasma Chemical Vapor Deposition Method [J]. Chin. Phys. Lett., 1998, 15(3): 228-229. [5] YIN Min, LOU Li-ren, FU Zhu-xi. Metalorganic Chemical Vapor Deposition of GaAs on Si Substrate Prepared by Room Temperature Chemical Cleaning Treatment [J]. Chin. Phys. Lett., 1997, 14(9): 690-693. [6] GAO Chun-xiao, ZHANG Tie-chen, ZOU Guang-tian, JIN Zeng-sun, YANG Jie. Epitaxial Growth of High Quality Diamond Film on the Cubic BoronNitride Surface by Chemical Vapor Deposition [J]. Chin. Phys. Lett., 1996, 13(10): 779-781. [7] SHI Hongtao, ZHANG Rong, ZHENG Youdou, HE Yuliang, LIU Xiangna. Cubic Silicon Carbite Film Growth and Characterization by HotFilament Chemical Vapor Deposition [J]. Chin. Phys. Lett., 1994, 11(11): 709-712. [8] GAO Kelin, ZHAN Rujuan, WANG Chunlin, CAO Jinxiang, XIANG Zhilin. Characteristics of the Plasma During Chemical Vapor Deposition for Diamond Growth [J]. Chin. Phys. Lett., 1992, 9(3): 144-147. [9] GAO Kelin, WANG Chunlin, ZHAN Rujuan, PENG Dingkun, MENG Giangyao, XIANG Zhilin. Growth of Diamond Films by Microwave Plasma Chemical Vapor Deposition [J]. Chin. Phys. Lett., 1991, 8(7): 348-351. [10] ZHAN Rujuan, GAO Kelin, ZOU Zuping, WANG Yanxia, LIU Jiezhou, XIANG Zhilin, LIU Hongtu, WU Zhiqiang, YE Jian, ZHOU Guien, WANG Changsui. GROWTH OF DIAMOND-LIKE FILMS BY DC PLASMA CHEMICAL VAPOR DEPOSITION [J]. Chin. Phys. Lett., 1990, 7(10): 445-448.
DownLoad: