A large volume copper vapor +HCI--H/sub 2/ laser with a high average power

A copper vapor laser tube with a large volume (15.1 L) has been built for the study of extrapolation in power of the Cu-Ne-HCl-H/sub 2/ laser medium. A high-power (77 kW) all-solid-state high-voltage power supply has been also used for this purpose. Results show an improvement of the optical power after the HCl-H/sub 2/ mixture injection. An optical power of 312 W has been extracted from this laser head in oscillator configuration.     

Compact hybrid master oscillator power amplifier with 3.1-W CW output power at wavelengths around 1061 nm

A hybrid master oscillator power amplifier (MOPA) laser source has been realized by coupling a single-mode three-section distributed Bragg reflector (DBR) laser as master oscillator and a tapered power amplifier with a single lens only. A maximum continuous-wave optical output power of 3.1 W was achieved. The emission spectrum was completely determined by the DBR laser. Single longitudinal mode operation at a wavelength of /spl lambda/=1061 nm was maintained over the whole power range. Up to an output power of 1.8 W, the beam propagation factor M/sup 2/was less than 1.6.     

GaAlAs／GaAs量子阱LD泵浦Nd：YAG激光器

利用分子束外延技术生长出了ＧａＡｌＡｓ／ＧａＡｓ折射率渐变分别限制单量阱材料。用该材料作出的激光二极管作泵浦源对Ｎｄ：ＹＡＧ激光器进行端面泵浦实验，在工作电流为３．３Ａ时，ＬＤ输出功率为２．７Ｗ，得到Ｎｄ：ＹＡＧ激光器的输出功率达７００ｍＷ，光－光转换效率达２０％。     

W级中红外宽调谐光学参量振荡器的研究

报道了一个低阈值、宽调谐、中红外单谐振掺MgO的周期性极化LiNbO3(PPMgLN)晶体光学参量振荡器(OPO)。利用声光调Q的Nd:YVO4激光器作为泵浦源,采用外腔结构,在室温下实现了PPMgLN晶体的准相位匹配(QPM)OPO。OPO阈值仅为0.4 W(重复频率40 kHz,单脉冲能量10μJ,脉宽160 ns);在泵浦光为6.6W(重复频率40 kHz,脉冲能量165μJ,脉宽65 ns)、PPMgLN周期为30μm时,获得了1.13 W的3.61μm中红外脉冲激光输出,光-光转化效率达到17.1%,同时获得了880 mW的1.51μm信号光输出,并且通过改变晶体的周期,实现了闲频光3.13～4.19μm中红外宽带可调谐激光输出。重点讨论了闲频光的功率、调谐和脉冲特性以及功率稳定性问题。     

Diode-pumped Q-switched Extra-cavity Frequency-doubled Nd：YVO4/KTP Green Laser

A diode-pumped acousto-optical（A-O） Q-switched extra-cavity frequency-doubled Nd：YVO4/KTP （KTiOPO4） green laser formed with a simple plane-plane cavity has been demonstrated. With the incident pump power of 12.7W, A-O Q-switched average output power at 1064nm was 3.81W with a duration of 25 ns at a repetition rate of 20 kHz, extra-cavity frequency doubling with KTP as the nonlinear crystal yielded the maximum output power of 1. 92 W at 532 nm, the corresponding optical conversion efficiency from 1064nm to 532nm light is 50.4%. The continuous-wave（CW） laser properties of diodepumped Nd：YVO4 crystal operating at 1064nm have been studied. With the incident pump power of 25 W, the maximum CW output power of 13.81 W was obtained with the corresponding optical conversion efficiency of 55.24%.     

High-Power and Widely Tunable All-Fiber Raman Laser

A high-power and widely tunable all-fiber Raman laser is demonstrated. The Raman fiber laser has been tuned over a range of 60 nm from 1075 to 1135 nm and delivers up to 5.0 W of Stokes output power for 6.5 W of launched pump power. Efficiencies ranging from 76.1 to 93.1% and laser thresholds from 0.78 to 2.59 W have been measured. The spectrum of the depolarized Raman gain coefficient of the germanosilicate fiber has also been inferred from our experimental measurements.     

Diode-pumped Q-switched Extra-cavity Frequency-doubled Nd: YVO4/KTP Green Laser

A diode-pumped acousto-optical(A-O) Q-switched extra-cavity frequency-doubled Nd: YVO4/KTP (KTiOPO4) green laser formed with a simple plane-plane cavity has been demonstrated. With the incident pump power of 12. 7 W, A-O Q-switched average output power at 1 064 nm was 3.81 W with a duration of 25 ns at a repetition rate of 20 kHz, extra-cavity frequency doubling with KTP as the nonlinear crystal yielded the maximum output power of 1. 92 W at 532 nm, the corresponding optical conversion efficiency from 1 064 nm to 532 nm light is 50.4%. The continuous-wave(CW) laser properties of diodepumped Nd: YVO4 crystal operating at 1 064 nm have been studied. With the incident pump power of 25 W,the maximum CW output power of 13.81 W was obtained with the corresponding optical conversion efficiency of 55.24%.     

多单元半导体激光器的高亮度光纤耦合输出

设计并研制了一种多单元半导体激光器的高亮度光纤耦合输出模块.激光器芯片采用分子束外延(MBE)方法生长的宽波导、双量子阱结构AlGaAs/GaAs激光器外延材料,激光器模块采用4只准直的单条形大功率半导体激光器,器件腔长为2 mm,发光区宽度为100μm,单条形器件的连续输出功率为5.0 W,每两只单条形器件的准直输出光束经过空间合束后再通过偏振合束,实现了多单元器件输出的高光束质量功率合成,采用简单的平凸透镜实现了合束光束与100μm芯径、数值孔径(NA)0.22石英光纤的高效耦合,耦合效率高达79%,输出功率达10.17 W,光纤端面功率密度达1.0×105W/cm2.     

155 W CW optical power from 1 cm monolithic AlGaAs/InGaAs laserdiode array

155 W continuous-wave output power from a 1 cm wide monolithic AlGaAs/InGaAs laser diode array with an emitting aperture of 4800 μm has been demonstrated at a cooling water temperature of 3°C. A continuous-wave output power of 72 W was achieved at room temperature with an emitting aperture of 1600 μm. High T₀ was observed for the laser structures     

Optimization of a UV Cu+ laser excited bypulse-longitudinal Ne-CuBr discharge

The discharge conditions for high average output power on four UV Cu⁺ lines at 248.6 252.9, 260.0, and 270.3 nm, in a nanosecond pulse-longitudinal Ne-CuBr discharge, have been investigated in two discharge tubes of different designs. A record average output power of 210 mW (and a peak pulse power of 1.7 W) on the 238.6-nm laser line, and of 270 mW for multiline operation has been obtained. An optical effect enhancing the 248.6-nm laser line power has been observed as the intensity of two Cu atom laser lines (510.6 and 578.2 nm) increases. It has been shown that the presence of Br atoms in the discharge leads to a fall of the Ne metastable density via Penning ionization and, hence, to a decrease of the Cu⁺ metastable density and an increase of the laser output     

Visible laser sources based on frequency doubling in nonlinearwaveguides

This paper reviews nonlinear quasi-phase-matching (QPM) waveguides and laser diodes with application to conversion of infrared laser diode wavelengths to the visible. The discussion of nonlinear QPM waveguides includes Ti-diffusion poled and E-field poled LiNbO₃ and KTP waveguides. Up to 25 mW of blue output power has been demonstrated for 120-mW infrared power injected into a nonlinear waveguide. Semiconductor laser sources suitable for frequency doubling are discussed, including distributed Bragg reflection (DBR) lasers operating at up to 200 mW output power, master oscillator power amplifiers with over 1 W output power, and wavelength-tunable flared semiconductor lasers with over 0.5 W output. A compact blue laser with 1-4 mW output power at 425-nm wavelength has been demonstrated based on a DBR laser frequency doubled in a nonlinear waveguide     

Single-frequency Ti:Al2O3 ring laser

Over 500 mW of single-frequency power has been obtained from a Ti:Al₂O₃ ring laser pumped by 10 W (all lines) from an argon ion laser. The ring laser can be tuned from 750 to 850 nm while maintaining more than 100 mW in single-frequency operation without realignment or a change of optics. The free-running frequency stability of the laser is 3 MHz. Thermal effects cause changes in the ring cavity parameters, limiting the output power. This ring laser has also been operated with an acoustooptic mode locker to obtain 200-ps mode-locked pulses at 250 MHz with nearly the same average power as in single-mode operation     

高功率激光二极管端面抽运复合晶体激光器的研究

在高功率激光二极管抽运固体激光器中,热效应已成为获得高输出功率和高光束质量的最大阻碍因素.用有限元方法研究了高功率激光二极管端面抽运Nd∶YVO4激光器中热透镜分布规律,提出了用复合晶体消除热透镜效应的方法.研究表明在端面抽运的传统单一Nd∶YVO4晶体激光器中,由于抽运功率密度很高,热透镜效应非常严重,由端面变形而造成的热透镜效应约占整个热透镜效应的50%;而采用复合晶体能够很好地消除由端面变形而造成的热透镜效应,同时得到很好的冷却效果,获得比采用传统单一晶体高出许多的基模输出功率和更好的光束质量.实验证明,采用复合结构晶体在23 W的抽运功率水平下得到了11 W的基模输出功率,光束质量因子M2 <1 5,光光转换效率达到48%.     

Tunable Q-switched/cavity-dumped Z-fold CO/sub 2/ waveguide laser with two channels and common electrodes

A tunable Q-switched/cavity-dumped z-fold CO/sub 2/ waveguide laser with two channels and common electrodes is studied. The Q-switched and cavity-dumped pulse lasers have been obtained from the z-fold channel with the tunable pulse repetition frequency (PRF) of 1-70 kHz. At the Q-switched operation, the peak power is 730 W and the pulsewidth is 150 ns at the PRF of 10 KHz. At the cavity-dumped operation, the pulse laser width can be adjusted. The peak power is 6000 W with the pulsewidth of 20 ns and 3400 W for 32 ns. CW laser output has been obtained from the other channel and its frequency can be tuned by a piezoelectric transducer. The Q-switched and cavity-dumped pulse laser heterodyne waveforms are observed.     

输出功率50 W的脉冲染料激光放大器

推导了准稳态下横向抽运的脉冲染料激光放大器的简化速率方程,提出了双侧横向抽运方式的脉冲染料激光放大器的设计原则和设计方法.应用高功率脉冲染料激光放大器的物理设计结果,研制了输出功率为50 W的脉冲染料激光放大器的实验装置.采用铜蒸气激光(CVL)作为抽运光,在此染料激光放大器上进行了实验研究,获得染料激光输出功率为52 W,抽运激光功率提取效率为41%.给出了染料激光波长、注入染料激光功率以及抽运激光的时间和空间匹配特性与染料激光放大器输出激光功率和抽运激光功率提取效率的相互关系,讨论了染料溶液浓度对双侧横向抽运方式的脉冲染料激光放大器的输出光束质量的影响.     

激光相干合成的研究进展:2011—2020

本文回顾了过去10年激光相干合成领域取得的重要进展,总结了可合成激光模块性能提升的标志性成果,梳理了相干合成使能技术取得的重要突破,展示了不同类型激光相干合成取得的成果及其多样化应用,并对激光相干合成领域的发展进行了展望。     

一种新型皮秒脉冲激光器

一种新型皮秒脉冲激光器由序列脉冲激光的产生、单脉冲激光的选取、放大和倍频等部分组成,激光器工作物质选用Nd∶YAG晶体,用两个格兰棱镜分别作为起偏器和检偏器,激光器的振荡级利用被动锁模染料产生的锁模序列脉冲激光,经过单脉冲选择器选取出其中的一个单脉冲激光,再经激光器放大部分的放大和倍频晶体的倍频后,激光器最终输出能量为120mJ,脉冲宽度为100ps,波长为532nm的单脉冲激光,其功率约为1.2×109W,功率密度约为4.2×109W/cm2,系统的外触发同步精度优于2μs。     

激光二极管抽运的Nd:NYW/LBO绿光激光器

报道了用激光二极管(LD)抽运的掺钕钨酸钇钠[Nd3 :NaY(WO4)2](简称Nd:NYW)绿光激光器。腔内采用Ⅰ类临界相位匹配LBO(LiB3O5)作为倍频晶体,阈值抽运功率为410mW,在抽运功率为1.5W时获得了87mW的530nm连续激光输出,基频光-光转换效率大于25%,斜率效率为7.98%。     

百瓦级1.2/1.5 μm双波长金刚石拉曼激光器（特邀）

具有高功率、高光束质量的双波长激光器在精密光谱、共振干涉测量和激光雷达等领域有着重要的应用。但是受到激光工作物质固有的光谱和增益特性制约,通过传统的粒子数反转激光器难以直接获得高功率的双波长激光输出,因此通常需要结合非线性光学频率变换技术将常规的单一波长高功率激光拓展至一个或若干个特殊波段。受激拉曼散射作为一种三阶非线性效应,具有频移大、自相位匹配和光束净化等优点,是实现高效率、高光束质量波长转换有效手段。利用具有宽光谱透过范围（>0.23 μm）、超高热导率（>2 000 W·m?1·K?1）和大拉曼频移（1 332 cm?1）等优异特性的金刚石晶体作为拉曼增益介质,通过外腔振荡结构实现了1 μm泵浦光直接向1.2 μm和1.5 μm双波长激光的高效转换,在最高稳态泵浦功率414 W的条件下获得了1.2 μm和1.5 μm功率分别为72 W和110 W的输出。该研究为实现高功率的双波长激光输出开辟了新的途径。     

Ar离子激光增强硅各向异性腐蚀速率的研究

研究了Ａｒ离子激光器与硅各向异性腐蚀技术相结合制造硅杯的方法。结果表明，激光照射能增强浸于ＫＯＨ溶液中硅的化学腐蚀速率，在入射光强为４．６Ｗ，ＫＯＨ溶液浓度为０．２２ｍｏｌ，温度为９０℃的条件下，得到＜１００＞硅的腐蚀速率为２１μｍ／ｍｉｎ，是无激光照射时硅各向异性腐蚀速率的多倍。进而讨论了硅在ＫＯＨ溶液中腐蚀速率对激光光强的依赖关系以及实验温度对腐蚀速率的影响问题。