55.0—200.0nm ZnⅡ,ZnⅢ,ZnⅣ真空紫外光谱

本文报道用1m正入射真空紫外光谱仪,在55.0～200.0nm范围内拍摄的ZnⅡ、ZnⅢ和ZnⅣ光谱。共观察到近400条谱线,辩认出Zn谱线213条,杂质元素谱线119条。特别是新归类了10条Zn谱线,其中ZnⅡ1条、ZnⅢ7条、ZnⅣ2条。     

氧碘化学激光器增益谱线的实验研究

 利用可调谐二极管激光器为探测光源, 直接测量了氧碘化学激光器的增益谱线的精细结构及其各谱线所占比例。同时用碘原子吸收池标定了六条谱线。     

液芯光纤中基于多线抽运调制的带宽可控平顶布里渊增益谱

提出在CS₂/CCl₄混合介质液芯光纤中利用多线抽运调制 技术实现带宽可控平顶布里渊增益谱的方法, 理论研究了抽运光谱线间距、谱线强度和芯液介质混合比对布里渊增益谱的影响, 得到了带宽可控平顶增益谱的条件. 结果表明, 采用一个强度或相位调制器, 基于单频和多频调制技术产生2–9条抽运光谱线, 通过控制谱线间距和各谱线强度比, 并改变CS₂体积分数, 获得了增益带宽在50 MHz–2 GHz 范围内可控的平顶增益谱. 该方法操作简便、带宽调控范围大, 可用于高增益低畸变布里渊放大, 满足微弱光信号探测和慢光系统的应用需求. 关键词： 受激布里渊散射 布里渊增益谱 多线抽运调制 液芯光纤     

三电极真空火花光源和高离化态原子谱线的产生与观测

本文敍述了我们新近建造的一台高电压、大电容、低电感三电极真空火花光源。用此光源与SGV-50真空紫外光谱仪相配合,分别用C、Al、Ti等元素作电极,进行了积分光谱的初步观测。在200A—2000A的波段区,辩认出高离化态谱线330条,其中C谱线174条,O谱线68条,N谱线44条,Al谱线24条,Ti谱线20条。实验表明,这种光源使用效果比较好。     

线聚焦激光辐照Al靶所产生的紫外X射线谱线

本文叙述了采用线聚焦激光幅照Al靶所产生的高离化态离子的紫外X射线(XUV)谱线。利用Cowan的原子能级程序计算了不同离化态的离子谱线的波长和振子强度gf,辨认出140条离子谱线,其中有82条新谱线。 关键词：     

一种内置法布里-珀罗标准具选择He-Ne激光器内谱线的方法

He-Ne激光器中633 nm波长的增益远大于该波段其它5条谱线的增益,而且由于模式竞争的影响,通常情况下增益较低的相邻弱线(如629 nm波长)很难出光.提出一种在He-Ne激光器中加入法布里-珀罗(F-P)标准具来选择输出谱线的方法.通过选择适当的F-P标准具长度和反射率,可以达到抑制强线增益,使弱线振荡输出的目的.还采用高斯光束传输理论对谐振腔内F-P标准具的透射特性进行了仿真计算.     

氮离子可见区新的激光跃迁

R.A.McFarlane[1]以空气放电获得六条氮离子激光谱线 ; Heard和 Peterson[2]用汞-氮放电在可见光蓝-绿区获得氮离子激光谱线; Cheo和Cooper[3]用脉冲放电方式获得氮离子激光谱线.本文以纯氮为工作物质,采用在脉冲放电回路中串入电感,拉长放电脉宽,适当降低放电峰值电流的技术,获得五条氮一次电离态的激光新谱线:其波长分别为 648.2,464.1,462.1,460.7,460.1毫微米.并对 NII 648.2毫微米谱线,研究了其激光强度与气压的关系,进行了电流及激光脉冲波形测量.激光脉宽比电流脉宽大得多,激光产生于放电余辉中,为复合激光. 本文用脉冲轴向放电…     

HT-6B托卡马克的真空紫外光谱

本文报导了HT-6B托卡马克在430～1300■的发射谱。所用光谱仪如247型掠入射真空紫外摄谱仪。共辨认出谱线一百多条。除工作气体氢的谱线外,主要是氧、碳和氮的各价离子的谱线。此外还发现了硫的谱线,并对这一谱线的存在提出了解释。     

约束冷原子气体的高增益Raman散射光谱

本文研究了不同外部环境中原子气体在强激光抽运下的相干Raman散射光谱, 通过对固定无反弹原子气体(不考虑外部自由度)和自由原子气体增益光谱的理论计算, 得到了和Mollow实验结果基本一致的光谱曲线.通过与Mollow谱线结构的比较, 揭示了在微阱约束情况下原子气体存在不同于以上两种环境的高增益光谱, 该谱线直接反应了约束阱的性质, 谱线呈等间距梳状结构, 谱线尖锐分辨率高, 和传统的冷原子气体散射增益光谱的实验结果相比较有更大量级的光增益现象. 论文还分析了散射谱线增益的物理机理, 清晰地给出了约束情况下原子增益谱线的非线性Raman共振条件.     

铕（Eu）原子的激光增强电离光谱的研究

本文从激光增强电离光谱的速率方程和ＬＥＩ光谱加宽理论出发，得到ＬＥＩ光谱信号和光谱轮廓的表达式，在紫外区测得铕的三条ＬＥＩ谱线。并用计算机模拟光谱的方法给出这三条谱线的轮廓，与实验所得的谱图一致。     

All-solid-state continuous-wave frequency doubling Nd:YAG/LBO laser with 8.2 W output power at 660 nm

An efficient and compact red laser at 660 nm is generated by intracavity frequency doubling of continuous wave (CW) laser operation of a diode pumped Nd:YAG laser at 1319 nm under the condition of suppression the higher gain transition near 1064 and 1319 nm under the condition of suppression the higher gain transition near 1064 and 1338 nm. With 40 W diode pump power and a frequency doubling crystal LBO, as high as 8.6 W of CW output power at 660 nm is achieved, corresponding to an optical-to-optical conversion efficiency of 21.5% and the output power stability in 8 h is better than 2.73%. To the best of our knowledge, this it the highest conversion efficiency of watt-level laser at 660 nm generated by intracavity frequency doubling of a diode end pumped Nd:YAG laser at 1319 nm.     

LaOBr:Ce,Tb中Ce3+对Tb3+发光的影响

近年来人们对LaOBr:Tb的合成及其发光特性的研究日益增多。LaOBr:Tb不仅是良好的X光增感屏材料,也是较好的阴极射线发光材料。为了进一步提高它的亮度,降低了b的含量(因Tb很贵),寻求LaOBr中Tb3+发光的敏化剂是很重要的。     

LBO Ⅰ类临界相位匹配内腔和频555 nm激光器

报道了全固态连续波555 nm激光器.555 nm激光是分别由Nd:YAG和Nd:YVO4晶体的946 nm和1342 nm谱线非线性和频产生,两条谱线在各自晶体对应能级跃迁分别为4F3/2-4Ⅰ9/2和4F3/2-4Ⅰ13/2.实验中采用复合折叠腔结构,利用LBOI类临界相位进行腔内和频,当注入Nd:YAG和Nd:YVO4晶体的泵浦功率分别为20 W和10 W时,获得1.06 W的TEM00连续波555 nm激光输出.4小时功率稳定度优于±3.3%.实验结果表明采用两种激光晶体进行腔内和频是获得激光的高效方法,并可以应用到其它两种激光晶体进行腔内非线性和频,获得更多不同波长激光输出.     

All-solid-state continuous-wave frequency doubling Nd:YLF/LBO laser with 2.15 W output power at 526 nm

An efficient and compact green laser at 526 nm generated by intracavity frequency doubling of a continuous wave (CW) laser operation of a diode pumped Nd:YLF laser at 1053 nm under the condition of suppression the high gain transition at 1047 nm. With 19.5 W diode pump power and a frequency doubling crystal LBO, as high as 2.15 W of CW output power at 526 nm is achieved, corresponding to an optical-to-optical conversion efficiency of 11.2% and the output power stability in 8 h is better than 2.87%. To the best of our knowledge, this it the highest watt-level laser at 526 nm generated by intracavity frequency doubling of a diode pumped Nd:YLF laser at 1053 nm.     

All-solid-state continuous-wave frequency doubling Nd:LuVO4/LBO laser with 2.17 W output power at 543 nm

Efficient and compact green-yellow laser output at 543 nm is generated by intracavity frequency doubling of a CW diode-pumped Nd:LuVO₄ laser at 1086 nm under the condition of suppressing the higher gain transition near 1064 nm. With 16 W of diode pump power and the frequency-doubling crystal LBO, as high as 2.17 W of CW output power at 543 nm is achieved, corresponding to an optical-to-optical conversion efficiency of 13.6% and the output power stability over 8 hours is better than 2.86%. To the best of our knowledge, this is the highest watt-level laser at 543 nm generated by intracavity frequency doubling of a diode pumped Nd:LuVO₄ laser at 1086 nm.     

Sr3Gd(PO4)3:Tm3+的真空紫外光谱特性

研究了Sr3Gd(PO4)3 : Tm3 和GdPO4 : Tm3 样品的结构特性、光谱特性.GdPO4 : Tm3 为单斜晶系,基质掺入铥离子后结构没有明显变化.GdPO4:Tm3 在164和210 nm附近有强烈的吸收峰.位于164 nm附近的强烈的吸收峰是归因于基质的吸收引起,210 nm附近的吸收峰则归因于Gd 的8S7/2-6GJ的能级跃迁.在164 nm真空紫外光激发下,样品于453及363 nm处有较强的发射峰,发射主峰位于453nm,属于Tm3 的1D2→3H4(22,123 cm-1)跃迁的典型发射.由于阳离子质量的不同,Sr3Gd(PO4)3:Tm3 在166 nm附近的激发峰高于GdPO4: Tm3 的同位置的激发峰,其在363 nm处的发射有明显减弱,而在453 nm处的蓝色发射有显著的增强.     

Intense laser-cluster interaction in the strong coupling regime

The interaction of noble gas clusters with moderately intense laser radiation at 100 and 800 nm is investigated via molecular dynamics simulations. It is shown that the laser-cluster interaction creates a strongly coupled plasma, which is characterized by a dominance of collisional processes. This has led to several findings. (1) A new heating mechanism is identified that explains the observation of unusually high-charge states in recent experiments with 100 nm radiation at DESY. We find that energy absorption takes place in the following cycle: many-body collisions resulting in an enhanced recombination of free electrons to exited states, and subsequent reionization. (2) Cluster interaction with 800 nm radiation is a promising system for investigating the transition from weakly coupled plasmas, where collective processes dominate, to strongly coupled plasmas. We achieve this transition by varying a single parameter: the laser intensity. The experimental and theoretical accessibility of laser-cluster interaction, thus, allows a systematic combined study of the interplay between collective and collisional processes.     

LiNbO3:Cr:ZnO晶体生长和光谱特性的研究

采用提拉法从近化学计量比的熔体中生长出尺寸为φ20 mm×50 mm的优质LiNbO3:Cr:ZnO(CZLN)晶体,其光学均匀度为7.59(10-5).进行了吸收和荧光光谱的测定研究.吸收谱测试表明:Cr3 离子在晶体中有2个宽且强的吸收带及1个微弱的吸收线,两宽带中心波长分别为480和660 nm,对应于4A2→4T1和4A2→4T2两个具有相同的总自旋能级之间的跃迁,在4A2→4T2吸收宽带的长波边缘处有个很小的吸收峰,其波长为727nm,对应于4A2→2E(R线)的跃迁.荧光测试表明:当激发波长为660 nm时,CZLN晶体荧光宽带和1个较弱的荧光线峰并存,宽带范围为802～988 nm,峰值波长为871 nm,对应于4T2→2E,4A2的联合能级跃迁,荧光线峰波长约为754 nm,其强度较弱,相应于2E→4A2(零声子线)能级跃迁.计算了晶场强度和Racah参数,其Dq/B=2.72,晶体属于强场介质.研究表明,CZLN晶体具备可调谐激光晶体的基本光谱要求,且有良好的物化性能,可以实现宽频带可调谐激光输出.它又具有较大的倍频系数,有望实现420 nm附近紫外的自倍频激光输出.     

All-solid-state continuous-wave frequency doubling Nd:LuVO4/LBO laser with 9.6 W output power at 672 nm

An efficient and compact red laser at 672 nm is generated by intracavity frequency doubling of a continuous wave (CW) laser operation of a diode pumped Nd:LuVO₄ laser at 1344 nm under the condition of suppression the higher gain transition near 1064 nm. With 38 W diode pump power and a frequency doubling crystal LBO, as high as 9.6 W of CW output power at 672 nm is achieved, corresponding to an optical-to-optical conversion efficiency of 25.3% and the output power stability in 8 h is better than 2.38%. To the best of our knowledge, this it the highest conversion efficiency of watt-level laser at 672 nm generated by intracavity frequency doubling of a diode pumped Nd:LuVO₄ laser at 1344 nm.     

不同波长激发下YLiF4：Er3+,Tm3+,Yb3+的发光

水热法合成了YLiF₄:Er³⁺,Tm³⁺,Yb³⁺,其中Er³⁺、Yb³⁺和Tm³⁺的摩尔分数分别为1%、1.5%和2%。当用355nm光激发时,其发光为蓝色,峰值位于450nm,对应于Tm³⁺的¹D₂→³F₄跃迁。用378nm激发时,发光为绿色,主要发光峰位于552nm。980nm光激发时,发光为白色,发光峰分别位于665(651),552(543),484,450nm处,并在648nm处还观察到了一个发光峰,其中最强的发射为红光。YLiF₄:Er³⁺,Tm³⁺,Yb³⁺的蓝光来源于Tm³⁺的激发态¹G₄到基态³H₆的跃迁,绿光来源于Er³⁺的⁴S_3/2和²H_11/2到基态⁴I_15/2的跃迁,红光既来源于Tm³⁺的¹G₄→³F₄的跃迁,也来源于Er³⁺的⁴F_9/2→⁴I_15/2的跃迁。在上转换发光中,还探测到了紫外光359nm的发射。监测665nm得到的激发光谱不同于监测552nm的激发光谱,在665nm的激发光谱中出现了对应Tm³⁺的¹G₄能级的峰。在双对数曲线中,蓝光484nm、绿光552nm和红光665nm的斜率分别为2.25、2.28和2.21,紫外光359nm的斜率为2.85。因此在980nm激发下,蓝光484nm、绿光552nm和红光665nm都是双光子过程,紫外光359nm的发射是三光子过程。