1.2 W中红外ZnGeP2光参量振荡器

报导了利用Tm,Ho:GdVO4激光器抽运双谐振ZnGeP2光参量振荡器实验研究.Tm(5%),Ho(0.5%):GdVO4晶体采用液氮制冷方式,工作在77 K温度条件下.以25 W波长为800 nm的光纤耦合激光二极管抽运,2 μm激光最大平均功率7 W,脉冲宽度小于30 ns, 脉冲重复频率5 kHz到20 kHz可调.非线性频率转换晶体ZnGeP2长15 mm,55?切割,OPO谐振腔为平平腔,腔长约25 mm.在5W的2 μm激光抽运下,脉冲重复频率10 kHz,实现了信号光3.7 μm及闲频光4.5 μm中红外激光输出,参量光脉冲宽度为15～17 ns,最大平均功率大于1.2 W,光-光转换效率为20%.测量参量光输出光束全宽度远场发散角4 mrad,光束质量M2因子小于3.     

高效率内腔式2 μm简并光学参量振荡器

报道了一种高效率的2 μm光学参量振荡器. 利用1.064 μm声光调Q Nd:YVO₄激光器抽运基于氧化镁掺杂周期性极化铌酸锂的内腔式光学参量振荡器, 在简并状态实现了稳定高效的2 μm激光输出. 当808 nm激光二极管抽运功率为20 W, Q开关工作频率为15 kHz时, 产生了平均功率为3.5 W、脉冲宽度为1.4 ns的2 μm激光, 光-光转换效率为17.5%, 斜效率为25%. 据我们所知, 该转换效率在2 μm波段内腔式光学参量振荡器中是最高的.     

高功率中红外3.8 μm激光器

 采用1.06 μm激光泵浦准相位匹配周期极化铌酸锂（PPMgLN）晶体光参量振荡器,实现高功率高效率高重复频率3.84 μm中红外激光输出。泵浦源为椭圆光斑1.06 μm激光,PPMgLN晶体MgO摩尔分数为5%,光参量振荡器为外腔单谐振结构,采用e→e+e相位匹配,利用了PPMgLN晶体的最大非线性系数。在1.06 μm激光功率为73 W,声光Q开关工作频率为7.5 kHz的条件下,获得平均功率8.3 W,波长3.84 μm激光输出,光-光转换斜率效率14.1％,水平和垂直方向光束质量平方因子分别为1.94,4.57。     

高重复率电光调Q的高光束质量Nd∶YVO_4板条激光器

部分端面抽运混合腔板条激光器可以在紧凑的空间内实现大功率高光束质量的激光输出。利用这一技术并结合具有增益高、荧光寿命短等特点的Nd∶YVO4晶体 ,配合新型高重复率的电光Q开关 ,易于实现高频窄脉冲高光束质量的激光输出。在德国EdgeWaveGmbH进行了混合腔电光调Q激光器的合作研究中 ,实现了高重复率近衍射极限的输出 ;在以 5kHz的高重复率运转时 ,获得了单脉冲能量 7 2mJ ,脉宽 5 7ns,平均功率约 36W的脉冲 ;当重复率高达 5 0kHz时 ,输出的激光脉冲的参量是单脉冲能量 1.6mJ,脉宽 9 5ns,平均功率超过 80W。实验所测的光束质量因子M2 小于 2。     

1.06 μm泵浦PPLT高重复频率人眼安全激光器

 利用1.06 μm光泵浦周期极化钽酸锂（PPLT）晶体获得1.54 μm激光。采用内腔式光参量振荡结构,利用V型腔优化谐振腔参数,分析了OPO晶体内光斑大小随激光工作物质热焦距的变化以及V型腔夹角对光束质量的影响。当泵浦电功率约为100 W时,获得高重复频率10 kHz、脉冲宽度125 ns、平均功率1.9 W的1.54 μm激光,电光转换效率约为1.9%。     

高重复率电光调Q的高光束质量Nd:YVO4板条激光器

部分端面抽运混合腔板条激光器可以在紧凑的空间内实现大功率高光束质量的激光输出。利用这一技术并结合具有增益高、荧光寿命短等特点的Nd：YVO3晶体．配合新型高重复率的电光Q开关．易于实现高频窄脉冲高光束质量的激光输出。在德国Edge Wave GmbH进行了混合腔电光调Q激光器的合作研究中,实现了高重复率近衍射极限的输出;在以5kHz的高重复率运转时．获得了单脉冲能量7．2mJ,脉宽5．7ns,平均功率约36W的脉冲;当重复率高达50kHz时．输出的激光脉冲的参量是单脉冲能量1.6mJ．脉宽9．5ns,平均功率超过80W。实验所测的光束质量因子M^2小于2。     

非临界相位匹配RTP晶体1.6μm光参量振荡器

采用非临界相位匹配切割,尺寸4mm×4mm×20mm的磷酸钛氧铷(RTP)晶体作为非线性光学晶体,进行了半导体激光端面抽运Nd:YAG/RTP的内腔式光参量振荡获得人眼安全激光的实验研究。对比了不同声光调Q重复频率下的信号光输出特性。在10.5W的抽运功率和15kHz的重复频率下,获得了最高900mW的1.62μm人眼安全激光输出,光光转换效率达8.6%。1.62μm信号光和对应的1.06μm基频光的脉冲宽度分别为4.6和8.2ns。信号光中心波长在1618nm,谱线宽度小于0.5nm。     

LD泵浦Nd~(3 )∶GdVO_4/Cr~(4 )∶YAG固体激光器

通过合理设计,精密调控各元件和温控电流,得到了平均功率为70mW,脉冲宽度为22ns,重复频率为14kHz,峰值功率高达230W的Nd3 ∶GdVO4/Cr4 YAG绿光脉冲激光器·腔外采用望远镜系统聚焦,经KTP晶体倍频后,得到了平均功率为28.8mW,脉冲宽度为19ns,重复频率为14kHz,峰值功率高达108W的绿光激光输出,转换效率高达·指出了小光斑对倍频晶体带来的影响·     

高平均功率调Q准连续Nd:YAG激光器

通过选用低掺杂浓度的Nd:YAG晶体棒、热近非稳腔优化设计、双棒串接热致双折射补偿技术以及双Q开关正交放置结构，在LD抽运功率1116W时，实现调Q准连续全固态Nd:YAG激光器1064nm输出，平均功率达258W，光束质量M²～15.5，重复频率为10kHz，脉冲宽度为64ns，峰值功率达0.4GW，光光转换效率达23.1%. 关键词： Nd:YAG激光器 准连续波 激光二极管抽运 固体激光器     

激光二极管抽运Tm,Ho∶YLF晶体声光调Q激光器

对激光二极管端面抽运Tm,Ho∶YLF晶体声光调Q激光器的激光特性进行了研究。根据粒子跃迁和能量传递过程,在考虑能级传递上转换的前提下,建立了Tm,Ho∶YLF脉冲激光器的速率方程,得到了初始反转粒子数的解析表达式,分析了能量传递上转换效应对激光上能级反转粒子数的影响。在室温下实现了2 μm波长激光的脉冲输出。实验上给出并分析了Tm,Ho∶YLF脉冲激光器的平均输出功率、单脉冲能量和脉冲宽度随抽运功率以及声光Q开关调制频率的变化关系。在抽运功率为2.8 W,重复频率为9 kHz时,获得了平均输出功率为189 mW的激光脉冲,光光转换效率为6.8%。在重复频率为1 kHz时,得到最大单脉冲能量为65 μJ,峰值功率为0.17 kW。     

Performance evaluation of ZnGeP2 optical parametric oscillator pumped by a Q-switched Tm,Ho:GdVO4 laser

A doubly resonant ZnGeP2 （ZGP） optical parametric oscillator （OPO） pumped by a novel Tm,Ho：GdVO4 laser was demonstrated. Cryogenic Tin（5 at.-%）, Ho（0.5 at.-%）：GdVO4 laser with high pulse repetition frequency （PRF） of 10 kHz at 2.05 μm was employed as pumping source of ZGP OPO. The 15-mm-long ZGP crystal, 55° cut for I-type phase-matching with low absorption coefficient less than 0.05 cm^-1 at 2 μm, was placed in a piano-piano cavity with resonator length of 30 mm. The ZGP OPO generated a total combined output power of 1.2 W at 3.75 and 4.52 μm under pumping power of 5.3 W, corresponding to slope efficiency of 40% from incident 2μm laser power to midinfrared （Mid-IR） output. A widely tunable range from 3.0 to 6.5 μm was achieved by changing the crystal angle only 3.5°.     

Comparative investigation of long-wave infrared generation based on ZnGeP2 and CdSe optical parametric oscillators

Long-wave infrared(IR) generation based on type-II(o→e+o) phase matching ZnGeP 2(ZGP) and CdSe optical parametric oscillators(OPOs) pumped by a 2.05 μm Tm,Ho:GdVO 4 laser is reported.The comparisons of the birefringent walk-off effect and the oscillation threshold between ZGP and CdSe OPOs are performed theoretically and experimentally.For the ZGP OPO,up to 419 mW output at 8.04 μm is obtained at the 8 kHz pump pulse repetition frequency(PRF) with a slope efficiency of 7.6%.This ZGP OPO can be continuously tuned from 7.8 to 8.5 μm.For the CdSe OPO,we demonstrate a 64 mW output at 8.9 μm with a single crystal 28 mm in length.     

A ring ZnGeP2 optical parametric oscillator pumped by a Ho:LuAG laser

We have demonstrated that we believe to be the first ring ZnGeP₂ (ZGP) optical parametric oscillator (OPO) pumped by a pulsed Ho:LuAG laser. The maximum output power of the ring ZGP OPO laser was 5.51 W at 13.1 W incident Ho pump power, corresponding to a slope efficiency of 59.0 %. The ZGP OPO laser produced 14 ns mid-infrared pulses in the 3.72–4.01 and 4.37–4.75 μm spectral regions simultaneously. In addition, the continuous wave Ho:LuAG laser generated 26.5 W of linearly output at 2,094.4 nm at the absorbed Tm pump power of 49.9 W.     

8.30 μm singly resonant ZnGeP2 optical parametric oscillators pumped by a Tm,Ho:GdVO4 laser

A single resonator 8.30 μm ZnGeP₂ (ZGP) optical parametric oscillators (OPO) was reported in the paper. The OPO was pumped by a 10.2-W Tm,Ho:GdVO₄ laser at 8 kHz in a Q-switch mode, a 170-mW idler was obtained at 8.30 μm, and the output power of the idler and signal wave was 1.0 W, corresponding to an optical-optical conversion efficiency of 10.3% and a slope efficiency of 20.9%. Tm,Ho:GdVO₄ laser was pumped by a 30-W fiber-coupled laser diode (LD) at the center wavelength of 801 nm. The output wavelength of Tm,Ho:GdVO₄ laser was at 2.05 μm, and the energy per pulse of 1.28 mJ in 18 ns was achieved at 8 kHz with the peak power of 71.1 kW.     

Comparative investigation of long-wave infrared generation based on ZnGeP2 and CdSe optical parametric oscillators

Long-wave infrared (IR) generation based on type-II (o→e+o) phase matching ZnGeP₂ (ZGP) and CdSe optical parametric oscillators (OPOs) pumped by a 2.05 μm Tm,Ho:GdVO₄ laser is reported. The comparisons of the birefringent walk-off effect and the oscillation threshold between ZGP and CdSe OPOs are performed theoretically and experimentally. For the ZGP OPO, up to 419 mW output at 8.04 μm is obtained at the 8 kHz pump pulse repetition frequency (PRF) with a slope efficiency of 7.6%. This ZGP OPO can be continuously tuned from 7.8 to 8.5 μm. For the CdSe OPO, we demonstrate a 64 mW output at 8.9 μm with a single crystal 28 mm in length.     

High-power,high-quality ZGP OPO pumped by a Tm,Ho:GdVO<Subscript>4</Subscript> laser

We report a ZGP OPO system capable of producing >6 W at a signal wavelength of 3.80 μm and an idler wavelength of 4.45 μm. The pumping source is the Tm,Ho:GdVO₄ laser operated at 2.049 μm with an M ² of 1.07. The ZGP OPO generated a total combined output power of 6.1 W at signal wavelength and idler wavelength under pumping power of 18.3 W, and an M ² of 1.7 for OPO output was obtained.     

A High-Power,Long-Wavelength Infrared ZnGeP<Subscript>2</Subscript> Opo Pumped by a <Emphasis Type="Italic">Q</Emphasis>-Switched Tm,Ho:GdVO<Subscript>4</Subscript> Laser

We report a high-power, long-wavelength infrared ZnGeP₂ (ZGP) optical parametric oscillator (OPO) pumped by a Q-switched Tm,Ho:GdVO₄ laser. The wavelength tuning range of 7.8–9.9 μm is realized by rotating the external angle of the ZGP crystal. We obtain an output power over 30 mW across the whole wavelength range and achieve a 1.71 W output power at 8.08 μm by transmitting the OPO parameters, corresponding to an idler laser slope efficiency of 12.1%.     

激光二极管抽运(Tm,Ho)∶YLF激光器光谱特性实验分析

Ho∶YLF晶体的5I7和5I8斯塔克能级分裂数较多,形成2047~2070nm宽的增益谱带,对于可调谐2μm激光及宽带激光放大器研究具有重要意义。理论上分析了(Tm,Ho)∶YLF晶体的能级结构,并对晶体掺杂浓度和长度进行了优化。实验研究了激光二极管抽运微片Tm(原子数分数0.06),Ho(原子数分数0.004)∶YLF激光谱线可调谐特性,调谐范围2.0656~2.0671μm。利用(Tm,Ho)∶YLF晶体的宽增益谱特性,将其作为激光二极管抽运激光放大器,成功地将2.048μm(Tm,Ho)∶GdVO4激光功率放大了2.5倍。实验上测量了(Tm,Ho)∶YLF晶体在强抽运条件下480~492nm及530~550nm可见波段的上转换蓝绿光荧光谱。     

二极管泵浦的2 μm高重复频率脉冲固体激光器

 报道了连续二极管端面泵浦2 μm高重复频率Tm,Ho:YLF激光器的实验研究结果。792 nm光纤耦合激光二极管作泵浦源,泵浦液氮制冷的Tm,Ho:YLF晶体。动态运转时,平均输出功率达到4 W,相应的能量抽取效率大于85%。采用声光调Q方式,重复频率1～50 kHz可调,10 kHz时,峰值功率达到12 kW,最小脉宽为32 ns。同时,还对二极管泵浦2 μm激光器设计中的各种因素进行了分析。     

磷锗锌光学参量振荡器技术研究

 报道了一台高重复频率2 mm光学参量振荡器泵浦的磷锗锌光学参量振荡器。磷锗锌晶体(ZnGeP₂,简称ZGP)采用Ⅰ类相位匹配方式,切割角度q为55°,f为0°,尺寸5.5 mm×6 mm×18 mm,在4.0 kHz重复频率下,当注入5.2 W的2 mm圆偏振光时,获得310 mW中红外输出,p偏振态2 mm到3～5 mm光-光转换效率12%。通过调节晶体的角度,实验获得ZGP光学参量振荡器的波长调谐曲线,在误差范围内与理论变化规律相符。