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摘要：
To study the selective erasure and writing of the multiplexed holographic storage in photorefractive crystals. According to the mechanism on forming of phase hologran in photorefractive crystal, by incoherently addition of the complementary hologram and the original hologram, the selective erasure and rewriting were accomplished. The complementary holography is an effective and convenient technique for selective erasure and rewriting of multiplexed holographic storage in photorefractive crystals.
作者：
Xie J.;Zhang Z.;He Q.;Wu M.;Jin G.
刊名：
Journal of Beijing Institute of Technology English Edition
在线出版时间：
2001

摘要：
Based on one-center model, the effects of the doping amount and the degrees of reduction and oxidation on the dynamic range M, the response time and the photorefractive sensitivity in the crystal LiNbO3:Fe are analyzed in detail. The principle of material optimization is discussed. The best crystal thickness (about 1.4-2.6 mm) for the maximum dynamic range M is calculated for the different doping amounts. The results show that the more the doping amount, the lighter the reduction of the crystal should be chosen, and that the heavier the reduction of the crystal, the less effect the doping amount has on the response time. The dynamic range M is in conflict with the response time. Due to the difficulty of processing crystals, the thickness is increased to 5 mm at the cost of decreasing the dynamic range M by 0.3-0.5.
作者：
Wang Jiangang;He Qingsheng;Jin Guofan;Wu Minxian
刊名：
Chinese Journal of Lasers B English Edition
在线出版时间：
2002

摘要：
A nonuniform photovoltaic field is created in Fe:LiNbO3during hologram recording exposures. Experimental results and analysis show the degradation of the volume holograms in the presence of the photovoltaic field. A sodium chloride solution is used to short-circuit the crystal to improve the storedimage quality. Experimental results to demonstrate the effectiveness of the proposed method are presented. © 2002 Optical Society of America.
作者：
He Qingsheng;Liu Guodong;Li Xiaochun;Wang Jiangang;Wu Minxian;Jin Guofan
刊名：
Applied Optics
在线出版时间：
2002

摘要：
A practical experimental system for two-centre recording by angular multiplexing and 90° geometry is designed with red and blue light. The erasure mechanism of lithium niobate crystals doubly doped with copper and cerium for two-centre recording is discussed and a modified decremental recording schedule for angular multiplexing is proposed subsequently. Finally, 50 nonvolatile holograms with almost the same diffraction efficiency are recorded.
作者：
Zhao Jian;Wang Jian-Gang;Liu Guo-Dong;He Qing-Sheng;Wu Min-Xian;Jin Guo-Fan
刊名：
Chinese Physics Letters
在线出版时间：
2003

摘要：
Increasing the data size of one page, storing more holograms and reducing the used space are the main methods to increase the data density to 5 Gbit/cm³.
作者：
Liu Guo-Dong;He Qing-Sheng;Huang Xiong-Bin;Wu Min-Xian;Jin Guo-Fan
刊名：
Zhongguo Jiguang Chinese Journal of Lasers
在线出版时间：
2003

摘要：
The principle of measuring magnetic fields with a ring laser system is discussed. The main source of error, the Zeeman effect, is studied, and a corresponding technique to reduce it is described. An experimental setup is developed with a Faraday cell of a large product of the Verdet constant and the length. The experimental device obtains a sensitivity of 0.5 nT and a stability of 2 nT. © 1992, Optical Society of America.
作者：
Feng T.;Jin G.;Zhang J.
刊名：
Applied Optics
在线出版时间：
1992

摘要：
By theoretical calculations we search the hold-on and hold-off state of the pulse-off electro-optic (EO) Q-switch made of La3Ga 5SiO14 (langasite, LGS) which exhibits both electro-optic (EO) effect and optical activity (OA), from which the proper applied voltage and orientation of LGS are determined. For the first time to our knowledge, a pulse-off EO Q-switch made of LGS is successfully designed and used in the Nd:YAG laser cavity. Q-switched pulses with energy 360 mJ and pulse width 8.3 ns are obtained, and the dynamic-static ratio is 80%. © 2005 Optical Society of America.
作者：
Liu Zhaojun;Wang Qingpu;Zhang Xingyu;Liu Zejin;Wei Aijian;Chang Jun;Su Fufang;Jin Guofan
刊名：
Optics Express
在线出版时间：
2005

摘要：
The electro-optic activity (EOA) of La 3Ga 5SiO 14 (langasite, LGS) crystal is studied theoretically and the result shows that the EOA will not change the rotatory power along the optic axis of the LGS: An experiment scheme called "elliptic analyzer" is used to verify this theoretical statement. The electro-optic effect (EOE) of the LGS crystal is also investigated in the same experiment and the EO coefficient r 11 is obtained to be 2.2 pm/y. © 2006 WILEY-VCH Verlag GmbH & Co. KGaA.
作者：
Liu Zhaojun;Wang Qingpu;Zhang Xingyu;Liu Zejin;Wei Aijian;Wu Fuquan;Chang Jun;Su Fufang;Fan Shuzhen;Jin Guofan;Tang Hengjing
刊名：
Physica Status Solidi A Applications and Materials Science
在线出版时间：
2006

摘要：
Optimisation of certain holographic 1 to N and 1 to N*N beamsplitters (Dammann gratings) with the aid of simulated annealing and damped least-squares algorithms is considered. Structures with N=5 to 53 uniform beams have been calculated. A photolithographic technique for fabrication of these elements is also presented, and its accuracy analysed with the aid of numerical simulations and actual test results. © 1988 IOP Publishing Ltd.
作者：
Turunen J.;Vasara A.;Westerholm J.;Jin G.;Salin A.
刊名：
Journal of Physics D Applied Physics
在线出版时间：
1988

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