高峰值功率重频脉冲固体激光器

综述了高峰值功率重频脉冲固体激光器的发展现状,对其中的Q开关、腔倒空、锁模等窄脉冲技术和放大技术进行了分析,展示了高峰值功率重频脉冲固体激光器的发展前景。     

高峰值功率重频脉冲固体激光器

综述了高峰值功率重频脉冲固体激光器的发展现状，对其中的Ｑ开关、腔倒空、锁模等窄脉冲技术和放大技术进行了分析，展示了高峰值功率重频脉冲固体激光器的发展前景。     

High repetition rate collisional soft X-ray lasers based on grazing incidence pumping

We discuss the demonstration of gain-saturated high repetition rate table-top soft X-ray lasers producing microwatt average powers at wavelengths ranging from 13.9 to 33 nm. The results were obtained heating a precreated plasma with a picosecond optical laser pulse impinging at grazing incidence onto a precreated plasma. This pumping geometry increases the energy deposition efficiency of the pump beam into the gain region, making it possible to saturate soft X-ray lasers in this wavelength range with a short pulse pump energy of only 1 J at 800-nm wavelength. Results corresponding to 5-Hz repetition rate operation of gain-saturated 14.7-nm Ni-like Pd and 32.6-nm line Ne-like Ti lasers pumped by a table-top Ti:sapphire laser are reported. We also discuss results obtained using a 1 /spl omega/1054-nm prepulse and 2 /spl omega/527-nm short pulse from a Nd:glass pump laser. This work demonstrates the feasibility of producing compact high average power soft X-ray lasers for applications.     

高重复频率锁模单脉冲选择器

本文报道了一个分别用电触发和激光触发的冷阴极管和Blumlein线路构成的锁模脉冲选择器,用纵向Z切割的LiNbO_3晶体做普克耳盒,获得了约50％的开关效率,消光比大于1000:1,选取单脉冲几率100％,半波电压3.2千伏,开关延迟时间30～60毫微秒,抖动小于2毫微秒。器件在10次/秒的重复率下经长时间运转,工作稳定可靠。     

High repetition rate pulsed gas lasers and their applications in chemistry and isotope separation

Presented in this paper are the results of experimental studies of pulsed high repetition rate XeCl, CO2, NH3, and CF4lasers with a closed gas cycle. Some applications of these lasers in chemistry and isotope separation are discussed.     

High repetition rate LC oscillator

LC oscillators have been built which can produce multikilowatt RF pulses in the megahertz frequency range with repetition rates of tens of kilohertz. The L and C for these oscillators can be determined from the frequency requirement and the high-Q requirements. The high repetition rates are achieved using a high-pressure spark-gap switch together with a dc to ac inverter power supply. Closely spaced antenna elements can be used to increase the number of cycles in the radiated waveforms (radiated Q).     

Electrically steerable lasers using wide-aperture VCSELs

A wide-aperture vertical-cavity surface-emitting laser has been fabricated so as to enhance the transverse mode selection. It was found that the far field emission can be made to exhibit two distinct steerable beams. The laser beams may be steered from 30° away from the normal right up to normal emission by varying the driving current. The steering effect is a thermal effect as confirmed by transient waveform analysis. A two-channel switch was built with switching time between channels of 10 μs and crosstalk of greater than 18 dB     

二极管端面抽运千赫兹激光器

大功率千赫兹激光器作为雷达系统的核心部分之一,在大气科学的研究中显得极为重要。实现大功率千赫兹激光器的可行方式之一是采用主振荡功率放大器。为了获得窄脉宽、高光束质量的千赫兹主振荡器,采用二极管端面抽运的千赫兹电光调QNd:YAG激光器的方法,进行了理论分析和实验验证,取得了重复频率1kHz、脉冲宽度5ns、单脉冲能量2.7mJ的1064nm激光输出,光光转换效率40%、光束质量M2=1.2。结果表明,该研究为1kHz,500W,10ns绿光主振荡功率放大器提供了合格的种子源。     

High repetition rate CH4 laser

A 16-μm CF₄ laser oscillator has operated at 1 kHz in a cooled static cell. Pump energies required from the low pressure, Q-switched, cw discharge CO₂ laser were as low as 60 μJ. The laser cavity employed a multiple-pass off-axis path resonator in a ring configuration. CF₄ laser power at 615 cm^?1 and a 1-kHz repetition rate exceeded 300 μW.     

High repetition rate burst-mode spark gap

Results are presented on the design and testing of a pressurized gas blown spark-gap switch capable of high repetition rates in a burst mode of operation. The switch parameters which have been achieved are as follows: 220 kV, 42 kA, a five-pulse burst at 1 kHz, 12-ns rise time, 2-ns jitter at a pulsewidth of 50 ns.     

重复频率YAG激光器泵浦腔的计算机辅助设计

本文提出了一种设计重复频率激光器泵浦腔的计算机绘图直观模拟方法—"双切线光路旋转法"。使用此方法可确定泵浦腔的聚光效率,腔体的尺寸,并可根据所用YAG棒径与棒长,确定与之匹配的泵浦灯径、灯长,还用计算机对泵浦腔冷却液通道的口径进行了模拟计算。     

Scaling of KrF lasers for inertial confinement fusion

The scaling and design principles for a MJ-scale krypton fluoride laser are derived and applied. First, the scaling limits of size and operation of a single large-aperture module (oscillator or amplifier) are explained, and its performance evaluated. A new scheme for combining amplifier modules into high output power chains is then presented. The performance of this architecture is investigated, showing that it effectively produces both the total energy and pulselength required for inertial confinement fusion using existing technology, while maintaining an easily manageable level of system complexity and acceptable low flux levels on optical elements.     

高重复率固体激光电源中的两个问题

本文讨论了谐振充电式重复率固体激光电源中存在的控制充电电压及防止“连通现象”出现的两个问题,并提出了有效的克服方法。     

High repetition rate electrooptic Q-switching of Nd3+:YAG lasers showing strong optical birefringence

Using a novel configuration of two coupled resonators, electroopticQ-switching of CW-pumped Nd³⁺:YAG lasers has been investigated. This technique yields two linearly polarized output beams with practically all the power contained in one beam. In the case of strong pumping, e.g., using high repetition rate flashlamp pumping, the optimization of mirror reflectivity leads to a single-resonator configuration.     

High repetition rate TEA CO2laser

This correspondence reports on the successful operation of a TEA CO2laser at rates up to 1000 pps with an average output power up to 65 W over long periods of time. An essential feature of the present system is a rapid gas circulation transverse to the laser axis combined with a large volume of ambient gas. It is found that decomposition of the gas is one of the major problems at high repetition rates.     

Return current in large aperture electron-beam-excited KrF lasers

Results from a model for an e-beam excited KrF laser are presented, and the effects of return currents on plasma parameters and laser performance are discussed. The author finds that the joule heating caused by the return currents, expressed as a fraction of total power deposition, increases with increasing halogen density, increasing aperture size, increasing pressure, and decreasing power deposition. The return current electric field causes a decrease in the rate coefficients for dissociate recombination and attachment and an increase in the rate of multistep ionization. As a result, the electron density near the foil increases by more than tens of percentage points. The laser intensity in those regions also increases. These effects are practically important in lasers having apertures exceeding 1 m     

高重复频率TEA CO2激光器

本文报导了一种封离式内循环高重复频率TEA CO2激光器的设计与制作,并给出了基本参数及初步实验结果.     

二极管泵浦的声光Q开关高重频Nd:YAG激光器研究

采用光纤耦合输出的连续激光二极管端面泵浦声光Q开关Nd:YAG激光器，在重复频率1kHz时，获得最窄脉宽5.5ns，最大峰值功率76kW；在重复频率20kHz时，最大平均功率4W（脉宽16ns），斜效率达33.4％。并对实验结果进行了讨论。     

Theoretical studies of UV-preionized transverse discharge KrF and ArF lasers

A theoretical model has been developed to examine the behavior of UV preionized, fast transverse discharge, rare-gas halide lasers. The model integrates the time dependent circuit equations for the discharge, the kinetic equations for the important atomic and molecular species and electrons, and the equations describing the growth of the spontaneous and stimulated emission. Results of KrF and ArF are compared with those in a companion experimental paper by Sze and Loree. The effects of various self-absorption mechanisms in the laser media are discussed, along with the possible impact of several uncertainties regarding the fundamental processes occurring in such lasers.     

An experimental and theoretical study of high repetition rate Q-switched Nd: YA1G lasers

An acoustooptic loss modulator made by bonding an X-cut quartz transducer to a fused silica scattering medium offers a practical means for repetitively Q-switching continuously pumped Nd : YAlG lasers at repetition rates up to 50 kHz. The peak power output of a multitransverse mode laser is typically enhanced by a factor of about 500 relative to CW operation at low (≪5 kHz) repetition rates and by larger factors when the transverse mode structure is suitably restricted. At high repetition rates, the peak power becomes smaller and the average power output approaches the CW level. The theoretical Q-switching behavior derived from the rate equations governing an ideal four-level laser is presented in graphical form, and is found to describe the observed behavior well when the laser is restricted to oscillation in the TEM00transverse mode. Similar calculations for Q-switched intracavity second harmonic generation indicate that the peak output power available at the second harmonic slightly exceeds that available at the fundamental, and that the harmonic coupling necessary to optimally couple the Q-switched laser is several orders of magnitude smaller than that required for CW intracavity conversion. Experiments using Ba2NaNb5O15For intracavity Q-switched harmonic generation roughly verified these predictions. A peak power output of 220 watts at 0.532 µ in the TEM00mode was achieved. Surface pitting of the nonlinear crystal after a few hours of operation prevented a thorough comparison with the calculated results. Preliminary experiments using the doubled Q-switched Nd : YAlG laser and an ammonia dihydrogen phosphate crystal to generate ultraviolet (the 0.266-µ harmonic) yielded a peak output power of 40 watts.