Maximum performance of discharge-pumped exciplex laser atλ=222 nm

The results of an experimental investigation into lasing and spontaneous emission from Ne(He, Ar)-Kr-HCl are presented. Evidence has been gathered of the effect of the pumping power, preionization rate, pumping pulse duration, and composition and pressure of the gas mixture on the lasing characteristics under discharge pumping. KrCl* formation efficiency is shown to be nearly half as much as for XeCl*. The output energy was 0.65 J for ~60 ns laser pulse duration (FWHM), 2.5% efficiency based on the pumping power, and 0.65% efficiency based on the stored energy while for the 10 ns pulse duration, 2.7% efficiency based on the pumping power and 0.8% efficiency based on the stored energy the output energy was 0.15 J. Recommendations are made for development of KrCl lasers with maximum output parameters     

Characteristics of pulsed discharges in copper bromide and copperHyBrID lasers

Comparative measurements of discharge electrical waveforms have been carried out with a Ne-H₂-CuBr laser, a Ne-CuBr laser, and a Cu HyBrID laser, each of the same size and geometry, and under the same conditions of excitation. From the general similarity of the electrical characteristics of the HyBrID laser and the Ne-H₂-CuBr laser, together with a reappraisal of the role of hydrogen, it is concluded that the main characteristics of these lasers (high efficiency, high average output power, and special features of their excitation pulse waveforms) can all be qualitatively explained if we assume that HBr and not hydrogen (molecular, atomic, or ionic) is the responsible agent which acts via the process of dissociative attachment of electrons to HBr during the interpulse period and during the early stages of the discharge current pulse     

用Cr~(4 ):YAG作被动调Q的准连续板条Nd:YAG激光器的性能研究

报道了用Ｃｒ４＋ＹＡＧ作被动调Ｑ，重复率为１００Ｈｚ的激光二极管泵浦的准连续板条ＮｄＹＡＧ激光器的性能。观察到调Ｑ脉冲的阈值泵浦功率、脉冲宽度、输出功率和调Ｑ效率均与泵浦脉冲的宽度有关。得到３７．４ｎｓ（ＦＷＨＭ）的调Ｑ脉冲。     

A miniature high-power KrF laser excited with a capacitively coupled discharge

A KrF excimer laser excited in a capacitively coupled discharge device made out of commercial BaTiO3doorknob capacitors is described. The discharge volume of 1.4 cm³is formed by a 3 mm bore into four capacitors glued together in a line. A maximal laser output energy of 1.7 mJ (1.2 J/l) in a 5.0 ns long pulse was achieved.     

Passive mode locked diode-pumped Nd:GdYVO4 laser with a GaAs absor ber

A passively Q-switched mode-locked Nd:GdYVO4 laser is successfully demonstrated by using a piece of GaAs crystalgrown at low temperature as the passively saturated absorber and the output coupler. Fundamental properties of the Nd:GdYVO4 laser are investigated. The maximum average output power of 3.5 W is obtained by using plainsphere when theincident pumping power is 10 W, which corresponds to an optical-optical coversion efficiency of 35%. The thresholdpower for the Q-switching mode-locked is 1.2 W. The maximum average output power of 1.72 W is obtained by usingGaAs when the incident pumping power is 10 W, mode-locked pulse train with a repetition rate of -113 MHz is achieved.At the incident laser pumping power of 7 W, the modulation depth is 100%.     

The N2+waveguide laser experiment and theory

The operation of an N+2ion waveguide laser (4278 Å) excited by charge transfer from He+2created in a capacitively coupled self-sustained discharge is described. In addition, the results of an experimental diagnostic program and a computer modeling program, conducted to explain the general operations of the discharge pumped He-N2system, are presented. The results of this program indicate upper laser level electron quenching and lower level pumping may be seriously limiting the achievable laser efficiency of this system. During the course of this study, it was found necessary to measure the pressure broadening coefficient of the N+2(B) rightarrowN+2(X) emission" by He. The value of this coefficient was found to be 3.5 MHz/torr ± 0.7 MHz.     

ArF准分子激光器的窄线宽可调谐运转及注入放大

在一台快放电泵浦的ＡｒＦ准分子激光振荡放大系统的振荡级上采用光栅、扩束镜、光阑等腔内元件，用组合输出镜获得了线宽小于０．１ｎｍ，调谐范围～１ｎｍ的激光输出。注入到非稳腔结构的放大级，注入后放大级效率提高了约５０％，获得了平均３０ｍＪ／脉冲的高光束质量的窄线宽可调谐激光，最大单脉冲能量＞５０ｍＪ，并进行了氧气的吸收光谱实验。     

880nm同带泵浦的高效率Nd:YVO4自拉曼激光器

利用880 nm半导体激光器同带泵浦声光调Q Nd:YVO4自拉曼激光器,以减轻热效应对泵浦功率的限制和对拉曼增益的影响,获得高效的1 176 nm一阶斯托克斯光输出。使用两块长度10 mm的Nd:YVO4晶体作为增益介质,脉冲重复频率190 kHz时,在26.8 W入射泵浦功率下获得6.11 W的平均输出功率,光光转换效率22.8%。实验研究了拉曼增益介质长度对输出功率和转换效率的影响,并对自拉曼激光器输出功率曲线中出现凹陷的原因进行分析,认为凹陷并非源自谐振腔稳定性,而是由于增益较弱的斯托克斯光对于谐振腔失调的敏感性所致。对照试验结果显示,与808 nm传统泵浦方式相比,880 nm同带泵浦下自拉曼激光器的输出功率和转换效率得到明显提高。     

Passive mode locked diode-pumped Nd:GdYVO4 laser with a GaAs absorber

A passively Q-switched mode-locked Nd：GdYVO4 laser is successfully demonstrated by using a piece of GaAs crystal grown at low temperature as the passively saturated absorber and the output coupler. Fundamental properties of the Nd： GdYVO4 laser are investigated. The maximum average output power of 3.5 W is obtained by using plainsphere when the incident pumping power is 10 W, which corresponds to an optical-optical coversion efficiency of 35%. The threshold power for the Q-switching mode-locked is 1.2 W. The maximum average output power of 1.72 W is obtained by using GaAs when the incident pumping power is 10 W, mode-locked pulse train with a repetition rate of - 113 MHz is achieved. At the incident laser pumping power of 7 W, the modulation depth is 100%.     

LD抽运Cr4+,Nd3+:YAG晶体获得1.4W自调Q激光输出

用激光二极管(LD)抽运Cr4+,Nd3+∶YAG晶体获得了1.064 μm的自调Q激光输出.激光输出模式为稳定的单纵模,抽运阈值功率为3.5 W,脉冲宽度为50 ns,斜率效率高达20%.当输入的抽运功率为10.8 W时,获得了1.46 W的自调Q激光输出.随着抽运功率的变化,脉冲宽度基本上保持不变,而重复率则在变化.     

激光二极管抽运的高效高重复频率Nd∶YAG陶瓷激光器

研制了激光二极管(LD)抽运的高效高重复频率声光调QNd∶YAG陶瓷微型激光器件。激光器采用激光二极管纵向同轴抽运Nd∶YAG陶瓷得到1064nm近红外激光输出,采用熔融石英作声光介质,声光调Q重复频率1Hz～115kHz可调。使用2W的激光二极管抽运,获得脉冲宽度16.4ns,峰值功率2.46kW,单脉冲能量40.5μJ的稳定运转。在重复频率110kHz时获得495mW的平均功率,总光光转换效率达24.75%。研究了重复频率及抽运功率对声光调Q脉冲激光器性能的影响,并对实验结果进行了相应的分析讨论,在理论上加以合理的解释。     

Diode-Side-Pumped Acoustooptic $Q$ -switched 1319-nm Nd:YAG Laser

In this paper, a diode-side-pumped acoustooptic Q-switched 1319-nm Nd:YAG laser is described. The output characteristics under the different repetition rates and output couplers have been studied. With a pumping power of 555 W, the average output power decreases from 94 W at 50 kHz to 71 W (slope efficiency 25.2%, optical conversion efficiency 12.8%) at 5 kHz. The highest peak power is up to 95 kW with the pulse duration of 150 ns at the repetition rate of 5 kHz.     

小型化高光束质量MgO: PPLN中红外光参量振荡器

为满足中红外激光的工程应用需求,研制了基于MgO: PPLN晶体的小型化高光束质量中红外光参量振荡器（MgO: PPLN-OPO）。泵浦源采用声光调Q Nd: YVO₄激光器,通过泵浦MgO: PPLN晶体,获得了高效率、高峰值功率中红外激光输出,在MgO: PPLN-OPO谐振腔中加入光阑,有效提高了中红外激光光束质量,整个激光器采用热电制冷与风冷相结合的散热方式,实现了激光器的小型化。实验结果表明:采用无水冷的声光调Q Nd: YVO₄激光器能够实现最高9.3 W的1.064 μm脉冲激光输出,光光转换效率为27.2%,峰值功率可达~27.5 kW;在Nd: YVO₄激光器泵浦下,MgO: PPLN-OPO实现了3.765 μm脉冲激光输出,在谐振腔中加入光阑后,MgO: PPLN-OPO的最高输出功率由1.20 W略降至1.08 W,但光束质量有明显提高,M_x2和M_y2因子分别从1.89和1.98优化至1.20和1.29,中红外激光脉冲宽度为8.4 ns,峰值功率达到~4.3 kW。     

单端光纤耦合的声光调Q全光纤化光纤激光器

实现了一种单端光纤耦合的高重复频率、窄脉冲、窄线宽及高效率的主动声光调Q全光纤脉冲光纤激光器。该光纤激光器基于光纤光栅与平面镜组合而成的线性法布里-珀罗(F-P)腔结构,采用激光二极管与(2+1)×1抽运耦合器形成后向抽运,并利用单端光纤耦合声光调制器(AOM)实现了全光纤化结构的脉冲掺镱双包层光纤激光器。调Q声光开关工作在一级方向,反向输出调Q脉冲,重复频率20～100kHz可调。在重复频率50kHz、抽运功率5.7W下系统获得了输出激光功率2.64W、单脉冲能量528μJ、脉宽56ns、峰值功率943W的稳定的高效率、窄线宽的窄脉冲,中心波长在1080nm左右,线宽为0.06nm,光-光转换效率高达46%。     

HF laser excited by a capacitively coupled discharge

A pulsed HF laser with gain volume on the order of 20 cm³has been excited by several independent capacitively coupled transverse discharges sharing the same optical resonator. Specific output energies of 200 μJ/cm³have been obtained, indicating a significant improvement over previous results, and output pulse lengths have been extended threefold through discharge sequencing.     

半导体激光泵浦Nd:YAG激光器技术研究

本文研究了半导体激光端面泵浦固体激光器中的主要技术,指出泵浦功率较低时,为了降低激光器的阈值应选用近半共心腔或大R腔;泵浦功率较高时,为了提高激光器的输出功率和转换效率应选用半共焦腔。泵浦光耦合系统的设计应满足与激光腔模的最佳模式匹配。当泵浦功率为86mW时,Nd;YAG激光器基模输出8.3mW;激光器阈值为12mW。     

半导体泵浦全固态紫外激光器

报道了LD泵浦Nd:YAG,经过KTP和LBO晶体中的倍频、和频,产生355nm紫外激光的全固态调Q激光器.当泵浦功率为100W,脉冲频率5kHz时,产生的1064nm基频光功率为20W,绿光功率为5.62W,输出450mW的紫外激光脉冲,转换效率为8%.     

Efficient quarter-Joule KrF laser with corona preionization

Conventional KrF excimer lasers which are pumped by means of an avalanche discharge use the ultraviolet radiation generated by a series of spark discharges to preionize the discharge region in order to obtain a uniform discharge. This paper describes the design and operating characteristics of a KrF avalanche-discharge laser which uses a corona discharge to preionize the discharge region. Such a preionization technique, along with the unconventional use of Ne rather than He as the buffer gas, has enabled this laser to generate overfrac{1}/{4}J of output energy with an overall efficiency of 1.3 percent while operating at a pulse rate of 2 Hz. This same general technique has enabled us to generate 55 W of average power from a gas transport KrF laser operating at higher pulse rates.     

Characteristics of the pumping pulse and the output laser pulse for a Cu/CuCl double pulse laser

Characteristics of the pumping discharge pulse and laser pulse in a Cu/CuCl double pulse laser have been measured as a function of time delay, buffer gas pressure, and tube temperature. We have found that for otherwise fixed discharge conditions, pumping rates decrease as these quantities are increased. The shape of the laser pulse as a function of time delay is shown to be dependent on the rate of current rise of the pumping pulse. The length of time required by the pumping pulse to achieve threshold is found to be a function of time delay, buffer gas pressure, and tube temperature. The implications of this behavior for the role of metastable copper and its mode of relaxation are discussed.     

高功率涡流稳弧闪光灯

我们研制成了用高速涡流气体产生的压力梯度场来稳定脉冲放电电弧的高功率涡流闪光灯。当工作氩气的流量为5升/秒时,已经实现了工作频率为110次/秒的万瓦放电。放电的峰值电流最大达20千安,放电闪光上升时间为1～1.5微秒,脉宽为3～4微秒,发光效率达30％。本文报告了这种灯的结构,灯的放电电路、灯内压力梯度场的分布、灯的电光特性和灯的功率平衡分析等结果。