单脉冲时间精确可控的单纵模Nd:YAG激光器  

Single-axial-mode Nd:YAG laser with precisely controllable laser pulse output time

作　　者：戴殊韬[1] 江涛[2] 吴丽霞[1] 吴鸿春[1] 林文雄[1] Dai Shu -Tao;Jiang Tao;Wu Li -Xia;Wu Hong -Chun;Lin Wen -Xiong(Fujian Institute of Research on the Structure of Matter,Chinese Academy of Sciences,Fuzhou 350002,China;China Aerodynamics Research and Development Center,Mianyang 621000,China)

机构地区：[1]中国科学院福建物质结构研究所,中国科学院光电材料化学与物理重点实验室,福州350002 [2]中国空气动力研究与发展中心,超高速空气动力研究所,绵阳621000

出　　处：《物理学报》2019年第13期122-126,共5页Acta Physica Sinica

基　　金：国家重点研发计划(批准号:2016YFB0701000,2017YFB1104500)资助的课题~~

摘　　要：报道了一种单脉冲输出时间精确可控的单纵模Nd:YAG激光器.该激光器谐振腔采用自滤波非稳腔结构得到TEM00模,利用磷酸钛氧铷电光晶体作为相位调制器来扫描腔长,通过种子注入的扫描-保持-触发技术锁定腔模,得到稳定的单脉冲输出时间精确可控的单纵模输出.该1064 nm激光器输出脉冲能量为50 mJ,脉冲建立时间48 ns,单脉冲输出时间抖动小于1%.用波长计WS7测量脉冲的波长和线宽,测量结果显示,波长计干涉仪干涉条纹清晰光滑,是典型的多光束干涉波形,显示波长为1064.40416 nm,线宽<0.5 pm(波长计的极限分辨率).同时以0.1 Hz的工作频率连续记录了1700发脉冲的波长,波长抖动小于0.1 pm(峰峰值).In recent years,high-energy single-axial-mode Q-switched lasers have been widely studied and applied because of their wide applications such as in nonlinear optics,laser spectroscopy and light detection and ranging(LIDAR).Many applications require a Q-switched pulse that has not only single axial mode but also can be synchronized with an external system.But two most commonly used methods(the build-up time reducing technique and ramp fire technique)are difficult to achieve single-axial mode operation.In this work,we apply the ramp-hold-fire technique to an injection-seeded Nd:YAG laser.The slave oscillator is a self-filtering unstable resonator(SFUR).The SFUR oscillator can achieve a smooth spatial profile TEM00 transverse mode.An RTP electro-optical crystal is adopted for intracavity phase modulator to modify the effective optical path length of the slave oscillator cavity.The seed-injection locking is realized by the ramp-hold-fire technique.The laser driver generates a pumping pulse.After a suitable time delay the driver is fired,a linear ramp voltage is applied to the RTP crystal.A photodiode detector monitors the interference signal.As soon as the interference peak is detected,the controlling electronics produces a stop signal.The ramp voltage on the RTP crystal is stopped and held at a fixed value.Then the Q-switch is fired at a set time,and finally single axial mode laser is demonstrated.Combining the advantages of intracavity phase modulation and Q-switch exact synchronization of the ramp hold fire technique,we obtain a narrow linewidth single-axial-mode laser pulse with precisely controllable output time.The laser is capable of generating 1064 nm pulse energy large than 50 mJ.The pulse build-up time is reduced by 31 ns to 48 ns.The pulse firing time is precisely controlled with jitter less than 1%.Then the frequency spectrum of the 1064 nm laser is measured with a commercial Fizeau wavemeter HighFinesse WS7.The multi-beam interference patterns of the pulse are shown to be smooth in the wavemeter.The wavel

关 键 词：单纵模 种子注入 相位调制 电光调Q 

分 类 号：TN248[电子电信—物理电子学]