LD泵浦Nd：YAG激光器的强度噪声特性研究

本文在理论研究了ＬＤ泵浦Ｎｄ：ＹＡＧ激光器的强度噪声特性，用传递函数的形式给出各种噪声湿源对激光器强度噪声的影响，计算结果指出，Ｎｄ：ＹＡＧ激光器输出的激光并非相干态光场，在几兆频率上存在高于散粒噪声基准几十ｄＢ的驰豫振荡噪声，在小于驰豫振荡频率范围，激光器的强度噪声基本上处于泵浦泵噪声水平。     

LD泵浦的Nd：YAG微片激光器实验研究

详细讨论了激光二极管泵浦的Ｎｄ：ＹＡＧ微片激光器输出的纵，横模特性，当泵浦功率小于７４０ｍＷ时，输出为单纵模，基横模，线宽达到仪器分辨极限２５ＭＨｚ。     

二极管泵浦的高效连续波基横模Nd：YAG激光顺

报道了用激光二极管端面泵浦的高效连续波ＴＥＭ００模Ｎｄ：ＹＡＧ激光器，最大输出为０．６５Ｗ，斜效率５１％，光－光效率最高达４０．６％，并给出了耦合力学系统和二极管泵浦Ｎｄ：ＹＡＧ激光器的器件结构。     

二极管泵浦的高效连续波基横模Nd：YAG激光器

报道了用激光二极管端面泵浦的高效连续波ＴＥＭ００模Ｎｄ：ＹＡＧ激光器，最大输出为０．６５Ｗ，斜效率５１％，光－光效率最高达４０．６％，并给出了耦合光学系统和二极管泵浦Ｎｄ：ＹＡＧ激光器的器件结构．     

LD泵浦的Nd∶YAG微片激光器实验研究

详细讨论了激光二极管泵浦的Ｎｄ∶ＹＡＧ微片激光器输出的纵、横模特性．当泵浦功率小于７４０ｍＷ时，输出为单纵模、基横模，线宽达到仪器分辨极限２５ＭＨｚ．     

Cr^4＋：YAG的可饱和吸收特性与被动Q开关性能研究

运用速率方程计算了Ｃｒ＾４＋：ＹＡＧ晶体的可饱和吸收特性参数，包括初始吸收系数，饱和吸收系数，饱和光强和损耗调制度，用Ｃｒ＾４＋：ＹＡＧ对脉冲和连续Ｎｄ：ＹＡＧ激光器进行了被动调Ｑ，在脉冲Ｎｄ：ＹＡＧ激光器上得到了８ｎｓ的调Ｑ激光脉冲，在连续Ｎｄ：ＹＡＧ激光器的调Ｑ中得到了间隔和幅度抖动小于５％的输出脉冲充列。     

LD汞浦Nd：YAG激光器的连续激光输出和高重复率调Q

用连续输出１Ｗ国产多量子阱激光二极管列阵（ＭＱＷ－ＬＤＡ）泵浦Ｎｄ：ＹＡＧ固体激光器，连续激光输出最大功率为１１２ｍＷ，光－光效率为１０．６％，斜效率为２０％，实现了连续泵浦高重复频率（１ｋＨｚ，４ｋＨｚ，１０ｋＨｚ）调Ｑ输出，最大峰值３５５Ｗ，最大平均功率为４３．７ｍＷ。     

激光二极管端面泵浦的调Q内腔倍频Nd：YAG激光器

报道了用两个１．５Ｗ激光二极管偏振耦合端面泵浦的声光调Ｑ内腔倍频Ｎｄ：ＹＡＧ激光器。输出５３２ｎｍ绿光重复频率１ＫＨｚ时，最大峰值功率为２．２３ＫＷ，最窄脉宽为１８ｎｓ，平均功率４０ｍＷ。最高重复频率３０ＫＨｚ。重复频率１５ｋＨＺ时，最高平均率１２８ｍＷ。对声光调Ｑ内倍频Ｎｄ：ＹＡＧ激光器的动态特性进行了理论分析及计算。     

LD泵浦Nd：YAG激光器的连续激光输出和高重复率调Q

用连续输出１Ｗ国产多量子阱激光二极管列阵（ＭＱＷ－ＬＤＡ）泵浦Ｎｄ：ＹＡＧ固体激光器，连续激光输出最大功率为１１２ｍｗ，光－光效率为１０．６％，斜效率为２０％．实现了连续泵浦高重复频率（１ｋＨｚ，４ｋＨｚ，１０ｋＨｚ）调Ｑ输出，最大峰值功率为３５５Ｗ，最大平均功率为４３．７ｍｗ．     

连续Nd:YAG激光高重复率电光调Q研究

研究了连续Ｎｄ：ＹＡＧ激光器中由于热效应使ＹＡＧ棒产生的双折射引起传输的线偏振光退偏为椭圆偏振光的退偏现象所产生的输出不稳定和多模的原因。电光调Ｑ技术被应用于连续氪灯抽运的Ｎｄ：ＹＡＧ激光器件。为了获得稳定、单模的输出,在谐振腔内放置了一对λ／４波片。通过实验研究,实现了重复频率１～６ｋＨｚ的窄脉冲激光输出,这将为连续抽运的Ｎｄ：ＹＡＧ激光器提供一种新的电光调Ｑ技术。     

LD泵浦单频种籽激光器及其线宽的测试

研究了 L D泵浦的单频种籽激光器。以 Nd:YAG和 Nd:YL F晶体为工作介质 ,采用微片腔的谐振腔形式 ,获得了 1.0 6μm和 1.0 5 3μm的单频激光输出 ,其输出功率分别为 90 m W和 10 m W。采用光纤延迟自零差拍法测量了单频固体激光的线宽 ,其线宽为 30 0 k Hz。     

LD抽运Cr,Tm,Ho∶YAG微片激光器单纵模运转特性的研究

研究了LD抽运的单纵模Cr,Tm,Ho∶YAG微片激光器,激光器厚度为1?mm,在用波长785?nm的LD进行端面抽运时,激光器阈值为1060?mW,单纵模激光最大输出功率为31?mW. 对激光器输出功率随温度变化特性进行了研究,验证了CTH∶YAG晶体的温度敏感性. 还研究了激光器的温度调谐特性,实验测得激光器的温度调谐系数为14?GHz/℃. 关键词： 激光光学 CTH∶YAG微片激光器 LD抽运 单纵模运转     

LD pumped Nd: YAG microchip lasers

A new experimental result obtained for the first time about LD pumped Nd: YAG microchip lasers in China is presented. The output power reached 62.5mW, when the input power was 340mW. The optical efficiency was 18%. The experimental setup and the unique characteristics of the laseers are given and discussed.     

高峰值266nm紫外激光器

报道了一种激光二极管(LD)端面泵浦的Nd:YAG声光Q开关高峰值功率266nm紫外激光器。该激光器采用紧凑的平平腔结构,LBO和BBO分别作为其二倍频和四倍频晶体。分别利用高偏振比LD阵列(40∶1)、低偏振比LD阵列(5∶1)及低偏振LD阵列腔内放置布氏片结构进行了实验。当注入功率为25W、调制频率为10kHz时,以上结构分别得到功率0.85,0.61和0.72W的266nm紫外光输出。其中,采用高偏振比LD阵列的输出功率最高,单脉冲能量为85μJ,脉宽为5ns,峰值功率高达17kW,泵浦光到紫外光的光-光转换率达3.4%。     

Characterization of laser processing of single‐crystal natural diamonds using micro‐Raman spectroscopic investigations

The application of lasers for processing diamond has revolutionized the diamond industry and its applications in microelectronics, microelectromechanical system (MEMS) and microoptoelectromechanical system (MOEMS) technologies. The process quality can be evaluated using spectroscopic techniques. In the present investigation, four different types of Q‐switched solid‐state lasers (with different beam parameters), namely, a lamp‐pumped Nd:YAG laser operating at 1064 nm, a lamp‐pumped Nd:YAG laser operating at second harmonically generated 532 nm, a diode‐pumped Nd:YVO₄ laser operating at 1064 nm and a diode‐pumped Nd:YAG laser operating at 1064 nm, have been employed for the processing of a single‐crystal, gem‐quality, natural diamond. The main objective behind the selection of these lasers with different beam parameters was to study the effect of wavelength, pulse width, pulse energy, peak power and beam quality factor (M² factor) on various aspects of processing (such as microcracking, material loss and cut surface quality) and their relative merits and demerits. The overall weight loss of the diamond and formation of microcracks during processing have been studied for the above four cases. The characteristics of the graphite formed during processing, elemental analysis, surface morphology of the cut surface and process dynamics have been studied using micro‐Raman spectroscopy and scanning electron microscopy (SEM). We observed that laser cutting of single‐crystal diamonds used for industrial applications can be accomplished without microcracking or surface distortion using Q‐switched Nd:YAG lasers. This allows direct processing without extensive postgrinding and polishing stages. Very efficient diamond processing is possible using diode‐pumped lasers, which results in the lowest possible breakage rate, good accuracy, good surface finish and low weight loss. From the micro‐Raman and SEM studies, it is concluded that the surface quality obtained is superior when diode‐pumped Nd:YVO₄ laser is used, owing to its extremely high peak power. The maximum graphite content is observed while processing with lamp‐pumped Nd:YAG laser at 532 nm. An overall comparison of all the laser sources leads to the conclusion that diode‐pumped Nd:YAG laser is a superior option for the efficient processing of natural diamond crystals. Copyright © 2006 John Wiley & Sons, Ltd.     

1.5-mum emissions from laser-diode-pumped Nd-doped microchip solid-state lasers

1.5-mum emissions from Nd:YAG, Nd:YVO(4), and LiNdP(4) O>(12) microchip lasers pumped by laser diodes have been observed. These coherent emissions are attributed to the effect of high-energy modified lattice vibration owing to the existence of Nd ions as well as to stimulated intracavity Raman scattering enhanced by the microchip configuration. A four-wave mixing process involving two lasing fields and a Stokes field was identified as the generator of new adjacent 1.5-mu;m emission.     

Development of high-repetition-rate LD pumped Nd:YAG laser and its application

High-average-power and high-energy lasers with good beam quality are fundamental tools for pumping high-peak and high-average-power ultrafast Ti:sapphire laser systems. Laser-diode (LD) pumped solid slate lasers with phase conjugation offer a unique combination of efficiency, reliability, and compactness. We present the design details and performance characteristics of a 360-W 1-kHz LD pumped Nd:YAG phase-conjugated laser. We also discuss the basic design aspects and present our preliminary experimental investigations on ultrashort-pulse laser systems.     

Comparative studies of semiconductor saturable absorber mirror mode-locking dynamics in pulsed diode-end-pumped picosecond Nd:GdVO4 and Nd:YAG lasers

Ultrashort pulses were generated in passively mode-locked Nd:YAG and Nd:GdVO4 lasers pumped by a pulsed laser diode with 10-Hz repetition rate. Stable mode-locked pulse trains were produced with the pulse width of 10 ps. The evolution of the mode-locked pulse was observed in the experiment and was discussed in detail. Comparing the pulse evolutions of Nd:YAG and Nd:GdVO4 lasers, we found that the buildup time of the steady-state mode-locking with semiconductor saturable absorber mirrors (SESAMs) was relevant to the upper-state lifetime and the emission cross-section of the gain medium.