层状多重Bragg光栅的光写入及其WDM特性研究
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摘要
DWDM(密集波分复用)技术是未来光网络的关键,也是大容量光通信及对现有网络扩容的最佳方案,其技术重点是在现有通信波长范围内,尽可能增加复用的波长通道数量。近年来,体全息Bragg光栅以其良好的角度及波长选择性和制作上的各种优势,为光波分复用器件的发展提供了一种新的思路和方法。本文在研究体全息光栅的光写入过程中,提出了基于层状多重Bragg光栅的解复用方法,并在此基础上探讨其特有的记录方式以及其红外通信波段的解复用衍射特性。其主要内容包括:
(1)阐述了光折变效应的产生机制和光折变Bragg光栅的形成机理:以体全息光栅的耦合波理论为基础,讨论了光折变晶体中体全息光栅的衍射效率,角度及波长选择性:从Bragg衍射公式出发探讨了体全息Bragg光栅用于波分复用时的波长关系及宽光谱应用时光栅的Bragg失配量。
(2)测量了三种LiNbO_3晶体的光谱透过率,并通过透过率及晶体参数计算了晶体的光谱吸收系数,从中选耿最适合于本文光栅写入实验的晶体;对晶体中体全息Bragg光栅的写入和擦除时间常数进行了测量,在此基础上对多重光栅的时间递减曝光序列进行了讨论。从实验中探讨折射率调制度、写入角对记录光栅衍射效率的影响;对于平面光及球面光写入的体全息光栅作了光波衍射分离实验,研究其分光特点。
(3)讨论了层状多重体全息Bragg光栅的光写入方法,并在实验基础上,对层状多重体全息Bragg光栅用于波分复用器的可行性进行了实验论证。利用空间复用和角度复用技术,在片状LiNbO_3:Fe晶体中写入了3层×8重Bragg光栅,并成功得到了它们在红外通信波段分离的衍射谱,对于其解复用滤波特性进行了测量和分析。
(4)提出了一种全新的制作特殊体全息光栅的光擦除法。利用该方法可以在LiNbO_3:Fe晶体c轴方向上写入周期性结构的体全息光栅,而这种光栅结构是普通的光栅记录方法所不能完成的。阐述光擦除法写入此类光栅的两步制作方法,并在实验中利用光擦除法在片状晶体里制作得到了体全息光栅。实验结果表明:该方法完全可行。
Dense wavelength division multiplexing(DWDM) is an important technology of choice for expanding capacity in optical fiber communication, and wavelength division multi/demultiplexers is one of the key elements in the fiber-optical networks. The volume Bragg grating is promising greatly to be applied to DWDM system and the demultiplexer based on the VBGs (volume Bragg gratings) shows that it can be used as one of advantageous multi-channel components because of its excellent angle and wavelength selectivities. A kind of multiple VBGs with layered structure and its fabrication method are presented here. According to the method, the layered multiple VBGs (volume Bragg gratings) were recorded in LiNbO_3:Fe crystals, and the infrared demultiplexing characteristics of the formed VBGs were measured and analyzed. The main contents are as follows:(1) The mechanisms of the photorefractive effect and the creation of photorefractive grating are explained. Based on the Kogelnik's coupled wave theory, the Bragg diffraction efficiency, the angle selectivity and wavelength selectivity of VBGs formed in photorefractive crystals are analyzed. According to the Bragg's diffraction formula, the relation of the demultiplexing angle on communication wavelengths to the writing angle of VBG, and the Bragg mismatching value during wavelength demultiplexing with wide spectra by employing VBG are discussed.(2) The spectral transmissivity and absorptivity for three slices of LiNbO_3 crystal were measured, and the optimal one among them was chosen for the writing experiment of VBGs. The holographic time constants were gained by recording and erasing a single grating in a slice of LiNbO_3:Fe crystal. According to the recording and erasing time constants, the exposure time schedule of superimposed gratings was achieved. It was experimentally investigated that the dependence of the diffraction efficiency of VBG on the refractive index modulation and the recording angle. The VBGs were recorded in the crystal by a parallel beam and a spherical beam, and the diffraction experiments were performed subsequently.(3) The recording approach of the layered multiple VBGs in LiNbO_3: Fe crystal was investigated in detail. Eight superimposed VBGs in three layers respectively were recorded alternately in a slice crystal, and the infrared filtering characteristics of 24 formed gratings were measured and analyzed. The experimental results show that the layered VBGs are promising to be employed for a multi-channel demultiplexer in the range of infrared communication.(4) According to the photorefractive properties of LiNbO_3:Fe crystal, the volume holographic grating with the grating vector normal to c-axis of the crystal are obtained hardly.
A new method—light erasing method presented in this paper can be applied to fabricate this kind of grating. According to the method, the theoretical analysis as well as experimental investigation was accomplished orderly. The experiment results demonstrate that the light erasing method for fabricating volume holographic grating with grating vectors normal to c-axis in LiNbC>3 crystal is feasible.
(1)阐述了光折变效应的产生机制和光折变Bragg光栅的形成机理:以体全息光栅的耦合波理论为基础,讨论了光折变晶体中体全息光栅的衍射效率,角度及波长选择性:从Bragg衍射公式出发探讨了体全息Bragg光栅用于波分复用时的波长关系及宽光谱应用时光栅的Bragg失配量。
(2)测量了三种LiNbO_3晶体的光谱透过率,并通过透过率及晶体参数计算了晶体的光谱吸收系数,从中选耿最适合于本文光栅写入实验的晶体;对晶体中体全息Bragg光栅的写入和擦除时间常数进行了测量,在此基础上对多重光栅的时间递减曝光序列进行了讨论。从实验中探讨折射率调制度、写入角对记录光栅衍射效率的影响;对于平面光及球面光写入的体全息光栅作了光波衍射分离实验,研究其分光特点。
(3)讨论了层状多重体全息Bragg光栅的光写入方法,并在实验基础上,对层状多重体全息Bragg光栅用于波分复用器的可行性进行了实验论证。利用空间复用和角度复用技术,在片状LiNbO_3:Fe晶体中写入了3层×8重Bragg光栅,并成功得到了它们在红外通信波段分离的衍射谱,对于其解复用滤波特性进行了测量和分析。
(4)提出了一种全新的制作特殊体全息光栅的光擦除法。利用该方法可以在LiNbO_3:Fe晶体c轴方向上写入周期性结构的体全息光栅,而这种光栅结构是普通的光栅记录方法所不能完成的。阐述光擦除法写入此类光栅的两步制作方法,并在实验中利用光擦除法在片状晶体里制作得到了体全息光栅。实验结果表明:该方法完全可行。
Dense wavelength division multiplexing(DWDM) is an important technology of choice for expanding capacity in optical fiber communication, and wavelength division multi/demultiplexers is one of the key elements in the fiber-optical networks. The volume Bragg grating is promising greatly to be applied to DWDM system and the demultiplexer based on the VBGs (volume Bragg gratings) shows that it can be used as one of advantageous multi-channel components because of its excellent angle and wavelength selectivities. A kind of multiple VBGs with layered structure and its fabrication method are presented here. According to the method, the layered multiple VBGs (volume Bragg gratings) were recorded in LiNbO_3:Fe crystals, and the infrared demultiplexing characteristics of the formed VBGs were measured and analyzed. The main contents are as follows:(1) The mechanisms of the photorefractive effect and the creation of photorefractive grating are explained. Based on the Kogelnik's coupled wave theory, the Bragg diffraction efficiency, the angle selectivity and wavelength selectivity of VBGs formed in photorefractive crystals are analyzed. According to the Bragg's diffraction formula, the relation of the demultiplexing angle on communication wavelengths to the writing angle of VBG, and the Bragg mismatching value during wavelength demultiplexing with wide spectra by employing VBG are discussed.(2) The spectral transmissivity and absorptivity for three slices of LiNbO_3 crystal were measured, and the optimal one among them was chosen for the writing experiment of VBGs. The holographic time constants were gained by recording and erasing a single grating in a slice of LiNbO_3:Fe crystal. According to the recording and erasing time constants, the exposure time schedule of superimposed gratings was achieved. It was experimentally investigated that the dependence of the diffraction efficiency of VBG on the refractive index modulation and the recording angle. The VBGs were recorded in the crystal by a parallel beam and a spherical beam, and the diffraction experiments were performed subsequently.(3) The recording approach of the layered multiple VBGs in LiNbO_3: Fe crystal was investigated in detail. Eight superimposed VBGs in three layers respectively were recorded alternately in a slice crystal, and the infrared filtering characteristics of 24 formed gratings were measured and analyzed. The experimental results show that the layered VBGs are promising to be employed for a multi-channel demultiplexer in the range of infrared communication.(4) According to the photorefractive properties of LiNbO_3:Fe crystal, the volume holographic grating with the grating vector normal to c-axis of the crystal are obtained hardly.
A new method—light erasing method presented in this paper can be applied to fabricate this kind of grating. According to the method, the theoretical analysis as well as experimental investigation was accomplished orderly. The experiment results demonstrate that the light erasing method for fabricating volume holographic grating with grating vectors normal to c-axis in LiNbC>3 crystal is feasible.
引文
1.黄章勇,新型光无源器件,北京邮电大学出版社,北京,2003,79～81
2. J. Minowa, Y. Fujii, Dielectric multilayer thin film filters for WDM transmission, J. Lightwave Technol, 1983, 1: 116～121
3. H. Takahashi, S. Suzuki, K. Kato, et al, Arrayed-waveguide grating for wavelength division multi/demultiplexer with nanometer resolution, Electronics Lett., 1990, 26(2): 87～88
4.徐宁榕,周春燕,WDM技术与应用,人民邮电出版社,北京,2002:63～65
5. K. O. Hill, G. Meltz, Fiber Bragg grsting technology fundamentals and overview, J. Lightwave Technol., 1997, 15: 1263～1276
6.顾畹仪,波分复用系统的发展和应用[J],电信科学,2001,(3):243～27
7. T. Erdogan, Fiber grating spectra, J. Lightwave Technol., 1997, 15: 1277～1294
8. D. Herre, M. Chauvet, J. E. Viallet, et al, First tunable narrowband 1.55um optical drop filter using a dynamic photorefractive grating in iron doped indium phosphide, Electron. Lett., 1994, 30: 1883～1884
9. R. T. B. James, C. Wah, K. Iizuka, et al, Optically tunable optical filter, Appl. Opt., 1995, 34: 8230～8235
10. S. Breer, K. Bsue, Wavelength demultiplexing with volume phase holograms in photorefractive lithium niobate, Appl. Phys. B, 1998, 66:339～345
11. P. Boffi, et al, 1550-nm volulne holography for optical communication devices. IEEE. Photonics Technology Letters, 2000, 12 (10): 1355～1357
12. J. W. An, et al, Volume holographic wavelength demultiplexer based on rotation multiplexing in the 90° geometry, Optics Communications, 2001, 197:247～254
13. P. Dittrich, G. Montemezzani, P. G.u nter, Tunable optical filter for wavelength division multiplexing using dynamic interband photorefractive gratings, Optics Communications, 2002, 214: 363～370
14. O. Beyer, I. Nee, F. Havermeyer, et al, Holographic recording of Bragg grating for wavelength division multiplexing in doped and partially polymerized poly(methyl methacrylate), Appl. Opt., 2003, 42: 30～37
15. D. Psaltis, C. Moser, G. Steckman, et al, Method and apparatus for implementing a multi-channel tunable filter, United States Patent Application Publication, 2002, Pub. No.: US0176126
16. A. Ashkin, et al, Optically-induced refractive index inhomogeneities in LiNbO_3 and LiTaO_3, Appl. Phys. Lett., 1966, (9): 72
17. F. S. Chen, J. T. LaMacchia, D. B. Fraser, Holographic storage in lithium niobate, Appl. phys. Lett., 1968, 12(7): 223～224
18. P. Yeh, Introduction to Photorefractive Nonlinear Optics [M], New York: John Wiley & Sons, 1993
19. P. Gunter, J. P. Huignard, Photorefractive Materials and Their Applications I [M], Springer-Verlag, 1988, Berlin
20.刘思敏,郭儒,凌振芳,光折变非线性光学,中国标准出版社,1992,3～4
21. 20. W. R. Klein, Theoretical efficiency of Bragg devices [J], Proc. IEEE, 1966, 54:803
22. B. H. Kogelnik, Coupled wave theory for thick hologram gratings [J], Bell System Technical Journal, 1969, 48(9): 2909～2974
23.陶世荃,王大勇,江竹青,等,光全息存储[M],北京工业大学出版社,1998
24. N. V. Kukhtarev, V. B. Markov, S. G. Odulov, et al, Holographic storage in electrooptic crystals, Ferroelectric, 1979, 22: 949～956
25. J. M. Heaton, P. A. Mills, E. G. S. Paigeetal, Diffraction efficiency and angular selectivity of volume phase holograms recorded in photorefractive materials, Opt. Acta., 1984, 31(8): 885～901
26. E. S. Maniloff, K. M. Johnson, Maximized photorefractive holographic storage, J. Appl. Phys., 1991, 70(9): 4702
27. S. Tao, D. R. Selviah, J. E. midwinter, Spatio-angular multiplexed storage of 750 holograms in an LiNbO_3 crystal, Opti. Soc. Am. J, 1993, 18(11): 912
28.方利华,高益庆,胡晓霖,等,光折变体全息存储研究,江西科学,2002,20(3):131～133
29.杨德兴,向红丽,赵建林,等,基于宽光谱应用的波长解复用多重体光栅的光写入特性,光子学报,2006,35(1):24～27
30.向红丽,分层Bragg光栅的制作及其波分复用特性研究,西北工业大学硕士论文,2005
31.刘思敏,郭儒,许京军,光折变非线性光学及其应用,科学出版社,2004,19～37
32.母国光,战元龄,光学,人民教育出版社,1984,188～189
33. A. Zylbersztejn, Thermally activated trapping in Fe-doped LiNbO_3, Appl. Phys. Lett., 1976, 29(12): 778～779
34. Y. P. Yang, Holographic recording and dynamic range improvement in lithium niobate crystals, California Institute of Technology doctor thesis, California, 2003, 1～7
35.覃鸣燕,陶世荃,梁宝来,等,掺铬KNSBN晶体的全息存储特性.2000.21(4):11～12
36. S. Fries, S. Bauschulte, Wavelength dependence of the electrooptic coefficients in LiNbO_3: Fe, , Physica Status Solidi (A) Applied Research, 1991, 125(1): 369～374
37. T. Loukina, Volume diffraction gratings for optical telecommunications applications: design study for a spectral equalizer, Opt. Eng., 2004, 43(11): 2658～2665
38.忽满利,周景会,李艳辉,等,密集型多重体全息光栅波长解复用技术,红外与激光工程,2004,33(3):317～320
39. A. Sato, M. Scepanovic, R. K. Kostuk, Holographic edge-illuminated polymer Bragg gratings for dense wavelength division optical filters at 1550 nm., Appl. Opt., 2003, 42(5): 778～784
40.曹良才,马晓声,何庆声,等,基于多重体全息光栅的光谱器件研究,光电子·激光,2003,14(2):114～117
41. Y. Taketomi, J. E. Ford, H. S. Sasaki, et al. Incremental recording for photorefractive hologram multiplexing, Opt. Lett., 1991, 16(22): 1774～1776
42. D. Psaltis, D. Brady, K. Wagner, Adaptive optical networks using photorefractive crystals, Appl. Opt., 1988, 27(9): 1752
43. A. C. Strasser, E. S. K. M. Johnson, et al., Procedure for recording multiple-exposure holograms with equal diffraction efficiency in photorefractive media, Opt. Lett., 1999, 14(1): 6～8
44.忽满利,李育林,刘玉华,等,多重全息存储中曝光均匀性的研究,激光杂志,1999,20(3):23～26
45.忽满利,刘玉华,刘继芳,等,光折变晶体均匀多重全息图存储研究,光子学报,1999,28(7):641～646
46.刘继芳,李育林,等,光折变晶体多重全息存储衍射效率均匀性的研究,光子学报,1997,26(5):428～433
47. W. J. Burke, P. Sheng, Crosstalk noise multiple thick-phase holograms, J. Appl. Phys., 1977, 48(2): 681～685
48. E. Chuang, D. Psaltis, Storage of 1000 holograms with use of a dual-wavelength method, Appl. Opt., 1997, 36: 8445
49. Dexing Yang, Hongli Xiang, Haibin Wang, et al, Multiple volume Bragg gratings with layered structure and their fabrication methods, Trends in Optics and Photonics Series (TOPS), 2005, 99—Photorefractive Effects, Materials, and Devices: 767～771
50. Haibin Wang, Dexing Yang, Jianlin Zhao, et al, Fabrication method of multiple VBGs with directly layered structure and its experimental demonstration, Proc. SPIE, 2006, 6149: 237-242
51. E. S. Maniloff, K. M. Johnson, Effects of scattering on the dynamics of holographic recording and erasure in photorefractive lithium niobate, J. Appl. Phys., 1993, 73(2): 541～547
52.杨德兴,光折变LiNbO_3晶体全息存储应用研究[A],西北工业大学硕士学位论文,1998
53. A. Glass, D. linde and T. Negran, High-voltage bulk photovoltaic effect and the photorefractive process in LiNbO_3, Appl. Phys., 1975, 8: 85～100
54. A. Novikov, S. Odoulov, O. Oleinik, et al, Beam-coupling, four-wave mixing and optical oscillation due to spatially-oscillating photovoltaic currents in lithium niobate crystal, Ferroelectrics, 1987, 75: 295～315
55. A. Krumins, et al, Opt. Commun., 1995, 117: 147
56.李家泽,阎吉祥,光电子学基础,北京理工大学出版社,1998,50～53
57. J. F. Nye, Physical Properties of Crystals[M], Clarendon Press, Oxford, 1979: 50-200
58. Dexing Yang, Jianlin Zhao, Enpu Li, Light-induced scattering of holographic write-in process in LiNbO_3: Fe crystal, Journal of Northwestern Polytechnical University, 2000, 18(2): 190～193
59. Dexing Yang, Haibin Wang, Jianlin Zhao, et al, Light erasing method for fabricating plane waveguide volume holographic gratings in LiNbO_3: Fe crystal, Proc. SPIE, 2006, 6149: 630-636
2. J. Minowa, Y. Fujii, Dielectric multilayer thin film filters for WDM transmission, J. Lightwave Technol, 1983, 1: 116～121
3. H. Takahashi, S. Suzuki, K. Kato, et al, Arrayed-waveguide grating for wavelength division multi/demultiplexer with nanometer resolution, Electronics Lett., 1990, 26(2): 87～88
4.徐宁榕,周春燕,WDM技术与应用,人民邮电出版社,北京,2002:63～65
5. K. O. Hill, G. Meltz, Fiber Bragg grsting technology fundamentals and overview, J. Lightwave Technol., 1997, 15: 1263～1276
6.顾畹仪,波分复用系统的发展和应用[J],电信科学,2001,(3):243～27
7. T. Erdogan, Fiber grating spectra, J. Lightwave Technol., 1997, 15: 1277～1294
8. D. Herre, M. Chauvet, J. E. Viallet, et al, First tunable narrowband 1.55um optical drop filter using a dynamic photorefractive grating in iron doped indium phosphide, Electron. Lett., 1994, 30: 1883～1884
9. R. T. B. James, C. Wah, K. Iizuka, et al, Optically tunable optical filter, Appl. Opt., 1995, 34: 8230～8235
10. S. Breer, K. Bsue, Wavelength demultiplexing with volume phase holograms in photorefractive lithium niobate, Appl. Phys. B, 1998, 66:339～345
11. P. Boffi, et al, 1550-nm volulne holography for optical communication devices. IEEE. Photonics Technology Letters, 2000, 12 (10): 1355～1357
12. J. W. An, et al, Volume holographic wavelength demultiplexer based on rotation multiplexing in the 90° geometry, Optics Communications, 2001, 197:247～254
13. P. Dittrich, G. Montemezzani, P. G.u nter, Tunable optical filter for wavelength division multiplexing using dynamic interband photorefractive gratings, Optics Communications, 2002, 214: 363～370
14. O. Beyer, I. Nee, F. Havermeyer, et al, Holographic recording of Bragg grating for wavelength division multiplexing in doped and partially polymerized poly(methyl methacrylate), Appl. Opt., 2003, 42: 30～37
15. D. Psaltis, C. Moser, G. Steckman, et al, Method and apparatus for implementing a multi-channel tunable filter, United States Patent Application Publication, 2002, Pub. No.: US0176126
16. A. Ashkin, et al, Optically-induced refractive index inhomogeneities in LiNbO_3 and LiTaO_3, Appl. Phys. Lett., 1966, (9): 72
17. F. S. Chen, J. T. LaMacchia, D. B. Fraser, Holographic storage in lithium niobate, Appl. phys. Lett., 1968, 12(7): 223～224
18. P. Yeh, Introduction to Photorefractive Nonlinear Optics [M], New York: John Wiley & Sons, 1993
19. P. Gunter, J. P. Huignard, Photorefractive Materials and Their Applications I [M], Springer-Verlag, 1988, Berlin
20.刘思敏,郭儒,凌振芳,光折变非线性光学,中国标准出版社,1992,3～4
21. 20. W. R. Klein, Theoretical efficiency of Bragg devices [J], Proc. IEEE, 1966, 54:803
22. B. H. Kogelnik, Coupled wave theory for thick hologram gratings [J], Bell System Technical Journal, 1969, 48(9): 2909～2974
23.陶世荃,王大勇,江竹青,等,光全息存储[M],北京工业大学出版社,1998
24. N. V. Kukhtarev, V. B. Markov, S. G. Odulov, et al, Holographic storage in electrooptic crystals, Ferroelectric, 1979, 22: 949～956
25. J. M. Heaton, P. A. Mills, E. G. S. Paigeetal, Diffraction efficiency and angular selectivity of volume phase holograms recorded in photorefractive materials, Opt. Acta., 1984, 31(8): 885～901
26. E. S. Maniloff, K. M. Johnson, Maximized photorefractive holographic storage, J. Appl. Phys., 1991, 70(9): 4702
27. S. Tao, D. R. Selviah, J. E. midwinter, Spatio-angular multiplexed storage of 750 holograms in an LiNbO_3 crystal, Opti. Soc. Am. J, 1993, 18(11): 912
28.方利华,高益庆,胡晓霖,等,光折变体全息存储研究,江西科学,2002,20(3):131～133
29.杨德兴,向红丽,赵建林,等,基于宽光谱应用的波长解复用多重体光栅的光写入特性,光子学报,2006,35(1):24～27
30.向红丽,分层Bragg光栅的制作及其波分复用特性研究,西北工业大学硕士论文,2005
31.刘思敏,郭儒,许京军,光折变非线性光学及其应用,科学出版社,2004,19～37
32.母国光,战元龄,光学,人民教育出版社,1984,188～189
33. A. Zylbersztejn, Thermally activated trapping in Fe-doped LiNbO_3, Appl. Phys. Lett., 1976, 29(12): 778～779
34. Y. P. Yang, Holographic recording and dynamic range improvement in lithium niobate crystals, California Institute of Technology doctor thesis, California, 2003, 1～7
35.覃鸣燕,陶世荃,梁宝来,等,掺铬KNSBN晶体的全息存储特性.2000.21(4):11～12
36. S. Fries, S. Bauschulte, Wavelength dependence of the electrooptic coefficients in LiNbO_3: Fe, , Physica Status Solidi (A) Applied Research, 1991, 125(1): 369～374
37. T. Loukina, Volume diffraction gratings for optical telecommunications applications: design study for a spectral equalizer, Opt. Eng., 2004, 43(11): 2658～2665
38.忽满利,周景会,李艳辉,等,密集型多重体全息光栅波长解复用技术,红外与激光工程,2004,33(3):317～320
39. A. Sato, M. Scepanovic, R. K. Kostuk, Holographic edge-illuminated polymer Bragg gratings for dense wavelength division optical filters at 1550 nm., Appl. Opt., 2003, 42(5): 778～784
40.曹良才,马晓声,何庆声,等,基于多重体全息光栅的光谱器件研究,光电子·激光,2003,14(2):114～117
41. Y. Taketomi, J. E. Ford, H. S. Sasaki, et al. Incremental recording for photorefractive hologram multiplexing, Opt. Lett., 1991, 16(22): 1774～1776
42. D. Psaltis, D. Brady, K. Wagner, Adaptive optical networks using photorefractive crystals, Appl. Opt., 1988, 27(9): 1752
43. A. C. Strasser, E. S. K. M. Johnson, et al., Procedure for recording multiple-exposure holograms with equal diffraction efficiency in photorefractive media, Opt. Lett., 1999, 14(1): 6～8
44.忽满利,李育林,刘玉华,等,多重全息存储中曝光均匀性的研究,激光杂志,1999,20(3):23～26
45.忽满利,刘玉华,刘继芳,等,光折变晶体均匀多重全息图存储研究,光子学报,1999,28(7):641～646
46.刘继芳,李育林,等,光折变晶体多重全息存储衍射效率均匀性的研究,光子学报,1997,26(5):428～433
47. W. J. Burke, P. Sheng, Crosstalk noise multiple thick-phase holograms, J. Appl. Phys., 1977, 48(2): 681～685
48. E. Chuang, D. Psaltis, Storage of 1000 holograms with use of a dual-wavelength method, Appl. Opt., 1997, 36: 8445
49. Dexing Yang, Hongli Xiang, Haibin Wang, et al, Multiple volume Bragg gratings with layered structure and their fabrication methods, Trends in Optics and Photonics Series (TOPS), 2005, 99—Photorefractive Effects, Materials, and Devices: 767～771
50. Haibin Wang, Dexing Yang, Jianlin Zhao, et al, Fabrication method of multiple VBGs with directly layered structure and its experimental demonstration, Proc. SPIE, 2006, 6149: 237-242
51. E. S. Maniloff, K. M. Johnson, Effects of scattering on the dynamics of holographic recording and erasure in photorefractive lithium niobate, J. Appl. Phys., 1993, 73(2): 541～547
52.杨德兴,光折变LiNbO_3晶体全息存储应用研究[A],西北工业大学硕士学位论文,1998
53. A. Glass, D. linde and T. Negran, High-voltage bulk photovoltaic effect and the photorefractive process in LiNbO_3, Appl. Phys., 1975, 8: 85～100
54. A. Novikov, S. Odoulov, O. Oleinik, et al, Beam-coupling, four-wave mixing and optical oscillation due to spatially-oscillating photovoltaic currents in lithium niobate crystal, Ferroelectrics, 1987, 75: 295～315
55. A. Krumins, et al, Opt. Commun., 1995, 117: 147
56.李家泽,阎吉祥,光电子学基础,北京理工大学出版社,1998,50～53
57. J. F. Nye, Physical Properties of Crystals[M], Clarendon Press, Oxford, 1979: 50-200
58. Dexing Yang, Jianlin Zhao, Enpu Li, Light-induced scattering of holographic write-in process in LiNbO_3: Fe crystal, Journal of Northwestern Polytechnical University, 2000, 18(2): 190～193
59. Dexing Yang, Haibin Wang, Jianlin Zhao, et al, Light erasing method for fabricating plane waveguide volume holographic gratings in LiNbO_3: Fe crystal, Proc. SPIE, 2006, 6149: 630-636