基于双晶匹配的低压铌酸锂电光削波器的研究  

Low Half-Wave Voltage Lithium Niobate Electro-Optic Slitter Based on Dual Crystal Matching

作　　者：吴婧 李清连 张中正 孙军[1,2,4] 张玲 隋展[5] 许京军 Wu Jing;Li Qinglian;Zhang Zhongzheng;Sun Jun;Zhang Ling;Sui Zhan;Xu Jingjun(MOE Key Laboratory of Weak-Light Nonlinear Photonics,Nankai University,Tianjin 300457,China;School of Physics,Nankai University,Tianjin 300071,China;TEDA Institute of Applied Physics,Nankai University,Tianjin 300457,China;Collaborative Innovation Center of Extreme Optics,Shanxi University,Taiyuan,Shanxi 030006,China;Shanghai Institute of Laser Plasms,ChinaAcademy of Engineering Physics,Shanghai 201800,China)

机构地区：[1]南开大学弱光非线性光子学教育部重点实验室,天津300457 [2]南开大学物理科学学院,天津300071 [3]南开大学泰达应用物理研究院,天津300457 [4]山西大学极端光学协同创新中心,山西太原030006 [5]中国工程物理研究院上海激光等离子体研究所,上海201800

出　　处：《中国激光》2022年第7期128-135,共8页Chinese Journal of Lasers

摘　　要：分析了电光削波器半波电压的关键影响因素,发现使用具有较大有效电光系数的电光晶体、合理设计晶体的横纵比是降低器件半波电压的有效手段;在此基础上,设计并制备出低半波电压的铌酸锂电光削波器。采用沿铌酸锂晶体x轴通光、z轴加电的横向电光工作模式,并利用双晶匹配的方式消除自然双折射的影响。匹配后两块晶体通光面的光学质量良好,直流高压下测得的半波电压约为900 V,动态消光比达200∶1。使用幅值为800 V、脉宽为0.95 ns、重复频率为1 Hz的脉冲高压驱动电光削波器工作时,从1064 nm连续激光中获得了脉宽为1.46 ns、重复频率为1 Hz的激光脉冲输出。Objective Electro-optic slitter is a type of laser pulse shaping device based on electro-optic effect.It is widely usedin laser amplification systems,nonlinear optical systems,laser fine machining,and other applications.At present,there are commercial slitters made of DKDP,BBO,RTP,KTP,and other electro-optical crystals.These slitters areaffected by crystal cutting type and working mode,whose aperture is between 2 and 20 mm,and the half-wavevoltage is several thousand volts or even ten thousand volts.The extremely high half-wave voltage greatly affects thepreparation and performance of the driving power supply.However,it is relatively easy to obtain an electrical pulsewith fast-rising time and narrow pulse width at low voltage for the driving power supply,thereby improving therepetition frequency of the device,reducing the power dissipation of the whole device,and reducing electromagneticinterference to other electronic devices in the system.Therefore,reducing the half-wave voltage positively improvesthe overall performance of the electro-optical slitter.The advantages and disadvantages of DKDP,BBO,RTP,KTP,and LN crystals are compared.From the requirements of the electro-optical slitter,LN crystal,as the corecomponent of the electro-optical slitter,is selected for designing and preparing the slitter.In this study,we designand fabricate a low half-wave voltage LN electro-optic slitter.Methods The electro-optic effect theory provides the electro-optic characteristics of LN crystal when an electric field is applied along each axis.The electro-optic effect is maximized using 90°x-cut crystals with radiation propagating and control voltage applied along the x-and z-axes,respectively.Also,we achieve a compensation of natural birefringence using two LN crystals whose z-axes are rotated relative to one another by 90°.A low half-wave voltage LN electro-optic slitter is fabricated and the optical quality,half-wave voltage,extinction ratio,and slitting performance of the slitter are measured and characterized.Results and D

关 键 词：非线性光学 铌酸锂晶体 电光效应 双晶匹配 削波器 

分 类 号：O734[理学—晶体学]