Output energy enhancement of discharge-pumped XeF(B to X) lasers with the two-component halogen donor mixtures

The effect of using a two-component halogen donor mixture was studied in a discharge-pumped XeF (B to X) laser using low-pressure (>     

Scaling characteristics of the XeF (C→A)excimer laser

The scaling characteristics and medium properties of an injection-controlled XeF(C→A) laser pumped by a 10-ns-high current density electron beam have been investigated. A five-component laser gas mixture, consisting of F₂, NF₃ , Xe, Kr, and Ar was optimized for the scaled laser conditions, resulting in 0.8-J output pulses at 486.8 nm, corresponding to an energy density of small-signal-gain measurements combined with kinetic modeling permitted the characteristics of the dependence of net gain on the electron-beam energy deposition and gas mixture composition, resulting in an improved understanding of XeF(C→A) laser operation     

Time-resolved spectroscopic study of high-pressure self-sustaineddischarge-pumped atomic xenon lasers

To explore the lasing kinetics of UV-preionized, self-sustained discharge-pumped atomic xenon (5d→6p) lasers, the time-resolved spectroscopy of the laser output from the multiline laser resonator is reported. The dilutents used were Ar and He. Increasing Xe concentration shortened the 1.73-μm laser pulse duration and decreased the total (multiline) laser output energy, because increased Xe metastable state population contributes to the increase of the 6p state population (lower laser level) by electron-impact excitation and radiation trapping during discharge pumping. High-excitation-rate pumping resulted in the decrease of the laser output power of 1.73- and 2.63-μm lines. Increasing the total gas pressure leads to high-efficiency operation due to modest-excitation-rate pumping at high pressures     

Gain studies of electron beam excited XeF laser mixtures

Detailed optical gain measurements of electron beam pumped Ar/Xe/NF3and Ne/Xe/NF3laser mixtures for theB rightarrow Xand theC rightarrow Atransitions of XeF at 351 and 488 nm are reported using a direct laser probe and two different fluorescence techniques.     

Measurement of lasing performance and efficiency of e-beam pumped xenon chloride

Ane-beam pumped XeCl laser has been operated in mixtures of Ne/Xe/HCl and Ar/Xe/HCl. Careful measurement of energy deposited by thee-beam was made to allow accurate determination of intrinsic medium efficiency. Laser output in neon was found to agree well with the predictions of a kinetics model, and yielded efficiency of 5-6 percent. In an argon diluent, we have found efficiency as high as 8.0 percent.     

XeF laser performance for F2and NF3fuels

XeF laser performance has been investigated for F2versus NF3as the halogen donor (fuel). The experiments were all performed in 3 AMAGAT Ne/Xe/fuel mixtures at ambient temperature and a pump rate of 132 KW/cm³on a 1 me-beam pumped laser. The F2-based laser mixture has been shown to be recyclable, with no loss in laser output, while laser performance steadily degrades for NF2-fueled mixtures under repetitively pulsed conditions. Despite the fact that F3absorbs at the XeF wavelength, it has been demonstrated that under appropriately chosen conditions the XeF intrinsic efficiency is essentially the same (2.2 percent) for both F2and NF3fuels for deposited energy loadings up to at least 150 j/l. Absorption, gain, fuel burn-up, and fluorescence were also measured in order to better characterize the laser medium and to determine the major factors contributing to the efficiency.     

Numerical modeling of the Xe Auger laser kinetics

A numerical model has been developed to describe various fundamental kinetics of an inner-shell excited Xe Auger laser emitted at 109 nm. We have found that the laser output characteristics strongly depend on the electron deexcitation of the upper laser level. This model also predicts the increase of the laser output energy by controlling a soft X-ray flux spectrum emitted from a laser-produced plasma     

射频激励金属板条波导CO2激光器的功率输出特性

为了获得较高的激光输出功率,介绍了射频激励扩散冷却全金属板条波导CO2激光器,放电区域由左右两个铝合金壁和上下两个铝合金电极构成,放电区域高2 mm,宽20 mm,长386 mm,工作气体混合比CO2:N2:He:Xe=1:1:3:0.26,该技术代替了过去的金属陶瓷结构,结合纵向电压均匀分布技术和面增比技术,获得了127 W的激光输出功率,光电转换效率高达14%。实验中,照相机放在激光器的纵向轴心上,清楚地记录了CO2激光器的放电现象。实验结果表明,该激光器小信号增益1%/cm,饱和光强1 200 W/cm2,促进了CO2激光器的发展。     

Improvement in the performance of an Ar-Xe laser using magneticspiker sustainer discharge excitation

In an X-ray preionized Ar-Xe laser using a magnetic-spiker sustainer discharge circuit with a magnetic pulse compressor a parametric investigation of the laser output versus gas composition and electrical excitation was performed. A considerable improvement in the performance of the discharge excited Ar-Xe laser was demonstrated. An output energy of 436 mJ was obtained from an active volume of 0.26 l at a total gas pressure of 1.8 bar containing 1% Xe in Ar with an overall efficiency of 2.1%     

150ns长脉宽XeCl准分子激光器的研究

通过采用多级Ｌ－Ｃ峰化回路、增大输出镜反射率、改变ＨＣｌ浓度的方法，使ＸｅＣｌ准分子激光的脉冲宽度达到１５０ｎｓ以上（最大脉宽达１７５ｎｓ），单脉冲能量大于１２０ｍＪ。同时对紫外准分子激光的光纤耦合系统进行了研究，直径为０．４，０．６，０．８，１．５ｍｍ的紫外石英光纤的耦合输出能量分别为１０，２９，３９，５８ｍＪ     

Analytic description of a homogeneously broadened injection laser

Analytic expressions for modeling the steady-state spectral output of homogeneously broadened lasers are presented. The expressions define the laser output in terms of the pumping rate, resonator reflectivities, arbitrary gain, spontaneous emission, and saturation profiles for each mode. To derive the analytic expressions the laser is idealized as a homogeneously broadened amplifier contained by a plane-parallel Fabry-Perot resonator. Rate equations are used to describe the interaction of the laser-mode intensities and population inversion over an infinitesimal section of the amplifier and differential equations describing the amplification of the modes as they pass through the gain section are deduced. Exact analytic solutions to these differential equations are found. These solutions, along with the boundary conditions imposed by the resonator, are used to specify completely the output of the laser. The model predicts a single-pass intensity gain which increases exponentially with pumping below threshold and saturates above threshold. An interesting result is that for a laser which is symmetric, an analysis which takesI^{+} = I^{-} = I, whereI^±are intensities traveling in the ± direction, gives results identical to an analysis which explicitly considers bothI^{+}andI^{-}, irrespective of the resonator mirror reflectivities. The predictions of the model are compared to the spectral output and single-pass intensity gain of a GaAs diode laser and found to be in good agreement. The laser model may be generalized in a straightforward manner to include feedback, compound cavities, and optical amplifiers.     

2-kHz repetition rate XeF laser

High-repetition-rate laser action, up to 2 kHz, has been demonstrated in XeF molecules at 351 and 353 nm by using a blowdown fast transverse-flow system and a four-circuit, thyratron-switched, low inductance pulse generator. For a typical run, the transverse flow was uniform, and the average flow velocity was 25 m/s across a discharge region of1.4 times 0.4 times 30cm³. The gas mixture used was He:Xe:NF3= 100:1.5:0.5, and the total pressure was varied from 600-1200 torr. For single-pulse operation, the maximum laser output energy was 22 mJ/pulse, and the electric efficiency was 0.4 percent. For a 2-kHz repetition rate, the average laser output energy was approximately 12 mJ/pulse with 50 percent variations. Hence, an average output power of 24 W was obtained.     

Effect of hydrogen on the average output power of the UV Cu/sup +/ Ne-CuBr laser

The effect of different additives-air, synthetic air, N/sub 2/, O/sub 2/, CO/sub 2/, He, Ar, Xe, and H/sub 2/, to the neon buffer gas on the average output power of a UV Cu/sup +/ Ne-CuBr is investigated. It is found that the addition of small amounts of hydrogen, 0.02-0.04 torr, leads to an increase by more than twice of the average output power for simultaneous laser oscillation at the five Cu/sup +/ lines-248.6, 252.9, 259.7, 260.0, and 270.3 nm.     

Nd:MgO:LiNbO/sub 3/ self-frequency-doubled laser pumped by a flashlamp at room temperature

A small Xe flashlamp-pumped Nd:MgO:LiNbO/sub 3/ self-frequency-doubled laser at room temperature is described. The laser device could be operated with 400 mu J/shot output of pure green light at 26 degrees C. The threshold is smaller than 4.8 J. The optimum phase-matching could be achieved over 15 degrees C to 45 degrees C, if the crystal was aligned and no photorefractive damage was observed.<>     

螺旋氙灯泵浦钛宝石激光器

本文报道了螺旋氙泵浦宝石激光器的特性,获得斜率效率0．078％、最大能量148．3毫焦的激光输出。并对不同实验条件下激光输出结果作了实验研究和定性分析。     

基于类金刚石沉积的短脉宽XeCl激光设计及脉宽分析

在气体配比HCl:Xe:He=0.12％:1％:98.88％实现了大功率短脉冲XeCl准分子激光器,以纳米异质结构、微观量子阱、表面微小尺度薄膜沉积,镀制金刚石薄膜、半导体薄膜、巨磁薄膜,及外延生长及后续的光刻、激光与物质的相互作用、等离子体研究为目的,设计了高能量、短脉宽脉冲放电激励的XeCl准分子激光器新型结构,完成了脉冲波形测试。试验结果表明:激光脉宽最短13ns,单脉冲能量450mJ,矩形光斑大小2cm×1cm,束散角3mrad,最高重复频率5 Hz。验证了激光器结构、动力学速率方程、总结出了饱和增益、脉宽规律。产生的短脉宽激光热融蚀效应小,类金钢石材料对基底形成了良好的等离子溅射羽辉。     

High temperature studies of electron-beam pumped argon-nitrogen laser characteristics

Gain and laser output power of an electron beam pumped Ar-N2mixture were measured over the temperature range 25 to 350°C. The gain is about 0.6 cm^-1at room temperature, and increases to almost 1 cm^-1at 250°C. The laser performance at elevated temperatures was determined using a specially designed high temperature resonator. The fluorescence yield and laser output are found to decrease monotonically with temperature.     

Nd∶MgO∶LiNbO_3晶体的折射率测量和室温自倍频激光器

本文首次报道Nd:MgO:LiNbO_3晶体的折射率、位相匹配角及其室温自倍频激光器的测量结果。在26℃时,用小型氙灯泵浦,获得了每个脉冲400μJ的纯绿光输出,阈值小于4.8J,器件工作温度范围为25℃到45℃,没有观察到光折变现象。     

电子束泵浦XeF(C→A)激光的实验研究

给出了电子束泵浦XeF(C→A)准分子激光的实验资料并作了一些初步分析,这些结果是在选用最佳混合气体(对应电子束横向激发采用8大气压Ar,16托Xe,8托NF3;对应纵向激发采用2大气压Ar,8托Xe,3托NF_3)条件下得到的。着重研究了光学谐振腔对宽带内波长调谐性和输出功率的影响。用纵向电子束激发,在74毫微米宽带范围内(从455毫微米到529毫微米)得到了连续可调谐的窄带激光输出。当用棱镜作为色散元件时,其线宽约为5毫微米;如果用衍射光栅代替棱镜则线宽可窄至1毫微米左右。     

A theory of the mode-locked, internally frequency-doubled laser

An AM mode-locked laser with a frequency doubler internal to the laser cavity is analyzed. Mathematical expressions are derived for laser pulsewidth, saturated gain, and second-harmonic output power. It is shown that the maximum second-harmonic power output available from the mode-locked laser is a factor ofsqrt{2}less than that available from an identical free-running laser. Numerical examples are given for an Nd:YAG laser with a Ba2NaNb5O15internal frequency doubler.