Efficient high-power diode-end-pumped TEM00 Nd:YVO4 laser

We demonstrate a compact and efficient diode-end-pumped TEM₀₀ laser with output power of 25.2 W for 52 W of incident pump power by use of a single YVO₄ crystal with a Nd concentration of 0.3 at.%. In Q-switched operation 21-W of average power at a pulse repetition rate of 100 kHz and ~1.1-mT pulse energy at a pulse repetition rate of 10 kHz were produced. At 10 kHz, the pulse width is around 10 ns and the peak power is higher than 100 kW     

激光二极管抽运Nd∶YVO4/YVO4复合晶体激光器

在高功率激光二极管(LD)抽运的情况下,对比分析了Nd∶YVO4/YVO4复合晶体和Nd∶YVO4单一晶体的激光特性。实验证明,复合晶体能够有效地降低晶体内的温度梯度,减小由端面变形带来的热透镜效应,获得比单一晶体高出许多的输出功率。采用Z型折叠腔,研究了Nd∶YVO4/YVO4复合晶体KTP倍频特性,当抽运功率为17W时,获得了6.23W的绿光输出,抽运光到绿光的转换效率高达37%。     

Oxide-confined vertical-cavity surface-emitting laser pumped Nd:YVO4 microchip lasers

In this letter, we demonstrate an experimental study of using a large area oxide-confined vertical-cavity surface-emitting laser (VCSEL) to pump a Nd:YVO₄ microchip laser. The maximum output power of 1.2 mW in TEM₀₀ mode is obtained with a pump power of 8.2 mW. Experimental results show that the complex transverse modal behavior of VCSELs in the higher injection current may cause an impediment of power scaling     

波长锁定878.6 nm LD调制泵浦Nd: YVO4自拉曼激光器

报道了一款基于调制共振泵浦技术的Nd:YVO₄自拉曼激光器。针对全固态自拉曼激光器中热效应严重导致的激光器输出功率及光光效率普遍偏低的问题,合理地将共振泵浦技术和调制泵浦技术相结合,实现了激光器的有效热管控,缓解了激光器的热效应,提高了泵浦上限,从而实现了激光器输出功率和光光效率的大幅提高。当泵浦源的调制频率为10 kHz、占空比为40%、平均泵浦功率为30 W、声光Q开关的调制频率为100 kHz时,获得了最大平均功率为8.57 W的1176 nm斯托克斯光输出,相应光光转换效率28.6%。相较于相同泵浦功率的连续泵浦机制下的实验结果,斯托克斯光平均输出功率提高了42%,光光效率提高了8.5%。实验结果表明:共振泵浦和调制泵浦技术相结合的方式可以有效缓解热效应,提高泵浦功率上限,从而提高自拉曼激光器的输出功率和光光效率。     

Heat generation in Nd:YVO4 with and without laser action

We present quantitative interferometric measurements of thermal lensing in a diode-pumped Nd:YVO₄ crystal with and without laser action. The thermal loading increased by two times when laser action was inhibited. The thermal loading was strongly dependent on upper laser-level loss mechanisms (e.g. nonradiative decay, quenching, and Auger recombination)     

基于Nd∶YVO4/Nd∶YLF组合晶体的双波长激光器研究

设计了基于Nd:YVO₄/Nd:YLF组合晶体的双波长(1047 nm和1064 nm)激光器。理论分析了 组合晶体双波长激 光器的速率方程,实验研究了在固定抽运条件下双波长激光器的温度输出特性。在实验研究 过程中设置抽运功率为600 mW,调节组合晶体热沉温度以1.0 ℃为间隔逐步增加,当热沉温度从 7.0 ℃增加至22.0 ℃时,激光器获得了频差 范围 为4.58 THz～4.63 THz、功率均衡度可调的双 波长信号 输出。在实验温度上升的范围内,频差最大值出现在8.0 ℃时,为 4.63 THz;频差最小值出现在21.0 ℃,为4.58 THz。 实验结果表明,频差随温度的变化稳定在4.60 THz附近。尤其的当 热沉温度处于17.8 ℃时,获得了功率均衡的、频差为4.58 THz的双波长信号输出,此时功 率为18.48 mW。这种超大频差的双波长激光器在提升功率之后可用于 外差拍频获取太赫兹波信号。     

Passively modelocked 77 GHz Er:Yb:glass laser

A compact diode-pumped passively modelocked 1.5 mum Er:Yb:glass laser with 77 GHz repetition rate and 3.0 ps pulse duration is demonstrated. The laser could serve as a pulse generator in future high-speed return-to-zero data transmission systems     

亚纳秒脉宽半导体泵浦电光调Q Nd:YVO4激光器

报道了一种利用半导体端面泵浦Nd:YVO4晶体并采用电光调Q的短腔激光器。通过理论分析和实验研究,确定了激光器的结构和参数,并证明使用电光调Q技术可以实现亚纳秒脉宽激光输出。在腔长20mm、重复频率为1～100Hz的范围内,获得脉宽小于600ps、单脉冲能量大于0.42mJ以及光束质量M2为1.9的100Hz激光输出,不稳定度小于±3%。     

大功率激光二极管端面抽运的Nd：YVO4激光器

报道了利用掺杂浓度为0．3at．-％，通光长度为10mm的Nd：YVO4晶体作为增益介质，带光纤耦合的激光二极管端面抽运的Nd：YVO4激光器。在抽运功率为27．365W时，获得了14．85W的TEM00模输出，光-光转换效率为60．49％，斜率效率达64．5％。在上述基础上对晶体的掺杂浓度和晶体长度对激光器性能的影响进行了分析。     

Phase-noise-driven instability in a single-mode microchip Nd:YVO4 laser with feedback

We report the instability behaviors of a single-mode microchip solid-state laser subjected to external feedback. Two kinds of instabilities, random chaotic burst generations and random sinusoidal burst generations, were observed experimentally in an LD-pumped microchip Nd:YVO₄ single-mode solid-state laser with fiber feedback. These results are totally different form those observed in laser diodes with delay feedback systems, which have been widely studied in the last decades. The main features were reproduced numerically by utilizing the Lang-Kobayashi equations with phase noise, indicating phase-noise-driven dynamic instabilities     

A 3.63 W Nd：YVO4 orange-yellow laser with intracavity sum-frequency mixing

A design of laser-diode array (LDA) end-pumped Nd:YVO4 laser that generates simultaneously wavelengths of 1064 nm and 1342 nm is presented, and by using type-I critical phase matching (CPM) of BiB3O6, 593.5 nm continuous-wave (CW) laser is obtained with intracavity sum-frequency mixing. The maximum laser output power can reach 3.63 W with the pump power of 27.5 W. The optical-to-optical conversion efficiency is up to 13.2%, which is the highest value at 593.5 nm by the intracavity sum-frequency ...     

全固化环形单频Nd:YVO4可调谐激光器

分析了Nd:YVO4激光晶体两平-平通光面自身的标准具效应对单频激光器调谐特性的影响.采用一通光面切成1°劈形的Nd:YVO4晶体来消除自身的标准具效应,通过调节插入谐振腔内的标准具,使半导体激光器(LD)抽运Nd:YVO4单频激光器的最大可调谐范围达到约100 GHz.     

基于Nd:YVO4/PPMgOLN的532nm紧凑型阵列激光器

为更适用于批量生产激光投影仪,需要一种具有结构紧凑、性能稳定与低成本等特点的绿色激光器作为绿光光源。采用光胶合的Nd:YVO4/PPMgOLN晶体棒作为增益介质和倍频晶体,结合一种新型焊接封装工艺,最终得到了一种紧凑型微片阵列激光器。该激光器3个激光光束共得到了223.7 mW的功率输出,每个激光光束都有良好的光斑分布和稳定性,且激光器包含两个内置TEC在内具有47 mm35 mm25 mm的紧凑尺寸。激光器连续工作2.5 h波动小于2.5%。各项性能可以充分满足激光投影仪绿光光源的要求,并便于低成本批量生产与后期维护。     

高重频掺钕钒酸钇激光器双程放大理论研究

为了提高高重频掺钕钒酸钇激光器的放大效率,提出了一种针对Nd:YVO₄单轴晶体的新型双程放大方式,采用法拉第隔离器与Nd:YVO₄晶体旋转45°放置的方式,使得种子激光在往返通过晶体时的线偏方向均为π偏振方向。结果表明,在100W抽运功率下,1W种子激光采用该双程放大方式的输出功率能够达到36.2W,放大效果较之偏振片与λ/4波片组成的双程放大结构提高了41.5%。本研究对以Nd:YVO₄单轴晶体为放大级的弱种子激光放大有重要意义。     

A low-threshold efficient KTA OPO by a fiber-coupled diode-end-pumped Nd:YVO4 laser

A low-threshold efficient high-repetition-rate eye-safe optical parametric oscillator(OPO) is presented.The OPO is based on an x-cut non-critically phase-matched(NCPM) KTA intra-cavity pumped by an acousto-optically(A-O) Q-switched Nd:YVO4 laser.At 10 kHz,the lowest threshold of 0.75 W and the signal power of 0.6 W are got,corresponding to the single pulse energy of 60 μJ and the peak power of 20 kW.Tuning the frequency,the maximum output power at 1536 nm is 1.03 W at 30 kHz with an optical-to-optical conve...     

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。     

三明治腔结构的Nd:YVO_4激光器

报道了一种三明治腔结构（Ｓａｎｄｗｉｃｈ－ｔｙｐｅｒｅｓｏｎａｔｏｒ）的ＮｄＹＶＯ４全固态激光器。用发射波长８０６ｎｍ的光纤耦合二极管激光器（ＬＤ）泵浦ＮｄＹＶＯ４晶体，泵浦光功率为７Ｗ时获得１．０６４μｍ连续波（ＣＷ）ＴＥＭ００模最大输出功率为３．７Ｗ，光学斜效率为６２％；将ＫＴＰ放入腔内倍频，当泵光为５．６Ｗ时，获得ＣＷ绿光输出６２０ｍＷ。光－光转换效率达１１％。     

半导体泵浦双通Nd:YVO4板条激光放大器

报道了一种高效率、结构紧凑型半导体泵浦Nd:Y VO₄板条激光放大器,主振荡器为被动调Q微片激光 器,在重复频率20kHz时,种子激光为平均功率为0.5W、脉冲宽度为2.43ns的基模激光。设计了分别针对泵 浦光和种子激光进行整形的激光放大器,匹配泵浦光模体积,实现高的能量提取效率和高增 益放大,并减 小热透镜效应。采用柱透镜对半导体激光器单bar发射的泵浦光进行整形,采用焦距为60mm的柱透镜, 对一通种子激光进行整形匹配泵浦光的模体积,采用焦距为75mm的 球透镜构成一组相传递系统,使二通 种子激光匹配泵浦光的模体积。在重复频率20kHz时,实现了平均功 率为6.3W、脉冲宽度 为2.52ns和光束质量M²为1.5的激光输 出,能量提取效率大于16%。     

Internally folded Nd:YAG and Nd:YVO4 lasers pumped bylaser diodes

An efficient, scalable, diode-pumped Nd laser design is reported. The gain element can be longitudinally pumped along five separate axes and is relatively simple to fabricate. Both Nd:YAG and Nd:YVO₄ gain media were evaluated. Using five single-stripe laser diodes to pump the Nd:YAG, 3.94 W of absorbed power produced 2.1 W CW at 1.06 μm. The slope efficiency was 54 percent and the output was TEM₀₀. The threshold power was 40 mW. No evidence of thermal saturation was observed up to the maximum pump power. Repetitively Q-switched operation is also reported. The maximum output power for Nd:YVO₄ obtained with 2.9 W of pump power was 1.3 W. The slope efficiency was 47 percent     

可调谐全固化折叠腔单频倍频Nd:YVO4激光器

采用三镜折叠腔,使用KTP晶体进行内腔倍频,在激光谐振腔内插入标准具,利用标准具的选模调谐特性和激光晶体自身的标准具作用,设计并研制了LD抽运连续内腔倍频可调谐Nd:YVO4全固化激光器,实现了稳定的单频绿光输出,抽运功率1.5W时最大单频绿光输出40mW,频率可调谐范围约200GHz.