Nd:YAG陶瓷与单晶4F3/2–4I13/2跃迁的弱谱线多波长激光性能对比

报道了基于半导体激光端面抽运Nd:YAG的⁴F_3/2–⁴I_13/2 跃迁的弱谱线多波长激光输出. 实验对比了透明陶瓷与单晶材料的激光输出特性, 表明透明陶瓷和单晶材料荧光谱强度的略微差异, 导致了多波长输出时相同两个波长之间的激光强度比在两种材料中的差异. 基于两种耦合输出镜片, 激光阈值都在2 W左右. 在13.5 W的抽运功率下, 基于Nd:YAG透明陶瓷获得了输出功率4.05 W、强度比1 :2的1338与1356 nm双波长激光和输出功率3.65 W、强度比13 : 1的1356与1414 nm 双波长激光, 斜率效率分别达33.9% 和31.9%.     

半导体激光无线传能中光伏电池转换效率

为选择合适的激光参量与光伏电池参量,以提高激光无线能量传输(LWPT)系统的能量转换效率,通过实验研究了LWPT系统中能量接收单元,也即光伏电池在半导体激光照射下的输出特性。通过波长为808 nm和915 nm的激光辐照GaAs和Si光伏电池,研究了不同激光功率密度、光伏电池温度、电池类型以及激光入射角度对光伏电池输出特性与能量转换效率的影响。实验中,在波长为808 nm的激光功率密度从0.06 W/cm2上升至0.37 W/cm2的过程中,Si电池的最大输出功率从0.12 W上升至0.32 W,能量转换效率从50.9%下降至21.2%;GaAs电池的最大输出功率从0.40 W上升到1.07 W,能量转换效率从57.9%下降至23.8%。随着激光功率密度的增加,光伏电池的输出功率先增加而后趋于饱和,但是高功率密度激光引起的电池温升会导致其光电转换效率的下降,所以激光功率密度的选择与光伏电池温度的控制是提高LWPT系统能量转换效率的关键因素。     

CW dye laser operation at 200 W pump power

A continuously operating jet stream dye laser was pumped by a multiwavelength-multimode argon-ion-laser with a pump power up to 200 W. Rhodamine 6G-chloride was dissolved in a water-polyvinylalcohol-ammonyx solution. The dye laser was prism-tunable between 560 and 650 nm with maximum output power at 600 nm. The maximum output power of the cw dye laser was 43 W without tuning element and 33 W with a prism placed inside the cavity. Operation of a jet stream dye laser with a pump power higher than 200 W and an efficiency of about 30% seems to be possible.     

Yb3+:Y2O3透明陶瓷激光器获得5 W连续激光输出

用带尾纤输出的激光二极管作为抽运源,采用端面抽运10％Yb^3 ：Y2O3多晶透明陶瓷的方式获得了连续激光输出。抽运阈值功率为5．6W,当陶瓷介质吸收的抽运功率为31．11W时,Yb^3 ：Y2O3多晶透明陶瓷获得了最大连续激光输出功率5．48W。光—光转换效率为17．6％,斜率效率为25％。同时在激光实验过程中,没有发现饱和现象,因此采用更高功率的激光二极管作为抽运源,陶瓷的激光输出功率会得到进一步提高。这一研究成果表明,多晶透明陶瓷是一种非常有潜力的激光增益介质。     

2277-W continuous-wave diode-pumped heat capacity laser

A high power continuous-wave (CW) diode-pumped Nd:YAG laser operated in heat capacity mode is demonstrated by use of two identical highly efficient diode-pumped laser heads placed in a plane-plane resonator. The laser heads are uniformly pumped with a five-fold symmetrical side-pumping configuration,and each head is able to output maximum output power of 2200 W at 808 nm. Under a total pump power of 4290 W, the output power of the laser at 1064 nm is up to 2277 W, corresponding to an optical-to-optical efficiency of 53.1%.     

Highly-Efficient Ho:S<Subscript>i</Subscript>Sc<Subscript>2</Subscript>O<Subscript>5</Subscript> Laser Pumped by a Narrow Line-Width Tm:YAP Laser at 1.94 <Emphasis Type="Italic">μ</Emphasis>m

We present a highly-efficient continuous-wave Ho:SSO laser pumped by a diode-pumped Tm:YAP laser with a narrow linewidth (NL) of 0.3 nm. With the free-running (FR) Tm:YAP laser, we obtain a maximum output power of 2.23 W at an absorption pump power of 7.2 W, corresponding to an optical conversion efficiency of 31% and a slope efficiency of 42.6%. With the NL Tm:YAP laser, we obtain a maximum output power of 2.88 W at the same absorption pump power. The optical conversion efficiency increases to 40% when the slope efficiency increases to 55.5%. The output linewidth of the Ho:SSO laser is 0.8 nm when we use the Tm:YAP laser with a narrow linewidth of 1.8 nm pumped by a FR Tm:YAP laser. The beam quality also changes from 1.31 to 1.22.     

Generation of a uniform high-density microwave plasma for CO2 lasers using orthogonal electric fields

To realize a CO₂ laser using a fast-axial-flow high-output-power microwave discharge excitation, we devised a technology for making the microwave discharge uniform by varying the oscillation direction of an electric field with time. We also verified the effectiveness of this technology. As a result, we succeeded in increasing the discharge uniformity to 70% of the laser-tube cross-sectional area and realized a high laser output power and a high laser efficiency. In the case of a microwave input power of 1450 W, a maximum laser output power of 273 W and a laser efficiency of 18.8% were achieved; in the case of a microwave input power of 1070 W, a laser output power of 214 W and a laser efficiency of 20.0% were achieved. At the time of maximum output power, a high input power density of 280 W/cm³, which is approximately 20 times that in a dc discharge method, was achieved. Thus, a high-output-power microwave-discharge-excited CO₂ laser has become feasible. PACS 42.60.By; 52.80.Pi     

低温GaAs被动调Q锁模Nd:Gd0.42 Y0.58VO4 混晶激光器特性研究

采用低温生长GaAs晶体作为被动饱和吸收体兼输出镜,实现了Nd:Gd0.42Y0.58VO4混晶激光器的调Q锁模运转.研究了Nd:Gd0.42Y0.588VO4激光器的基频运转特性.在输出镜透射率T=10%、腔长L=40 mm的情况下,当抽运功率为8.6 W时,获得激光输出功率3.78 W,光-光转换效率为43.9%.并测量了Nd:Gd0.42Y0.58VO4混晶被动调Q激光器的输出特性.实验结果表明激光器调Q运转阈值为2 W,当抽运功率为3.7 W时,激光器出现调Q锁模行为;当抽运功率为8.6 W时,激光器调Q锁模深度达70%以上,对应的脉冲包络重复频率为670 kHz,半峰全宽为180 ns,平均输出功率为1.35 W,光-光转换效率为15.7%.     

Yb∶Y_2O_3陶瓷薄片激光器获得10.5 W连续激光输出

室温下采用中心波长约970 nm准直输出的大功率激光二极管模块作为抽运源,端面抽运双程吸收的腔型结构,抽运原子数分数为8%的Yb:Y2O3多晶透明陶瓷片获得连续激光输出。抽运阈值功率为7 W,当抽运功率达到35 W时,获得优化连续激光输出功率为10.5 W,光光转换效率为30%,斜率效率为37.5%。激光输出功率随抽运功率基本呈线性增长。采用更高功率抽运源、优化谐振腔结构和减小热效应的影响,Yb∶Y2O3陶瓷激光器的输出功率和效率将会得到进一步提高。     

Continuous wave operation of singly-doped Ho:LSO laser at room temperature

We present the room-temperature continuous-wave Ho:LSO laser single-pass-end-pumped by a diode-pumped Tm:YLF laser at 1.91 μm in this paper. Under different output couplers of 2.4, 5.0, and 14.0%, the laser output power and output spectrum of Ho:LSO laser operating at room temperature are investigated. The output wavelength of Ho:LSO laser was centered at 2106.5 nm with linewidth (FWHM) of about 3.2 nm. With T = 5.0%, the maximum output power of 2.4 W was achieved under the absorbed pump power of 11.1 W, corresponding to a slope efficiency of 38.0%.     

国产全光纤结构激光器实现245 W高功率激光输出

 以国产掺镱光纤为增益介质,利用国产泵浦源和光纤器件,构建了主振荡功率放大（MOPA）结构的全国产大功率全光纤激光器。激光器包括10 W种子激光器和高功率放大器两部分。在注入最大泵浦功率为356 W时,获得了245 W波长1 080 nm激光的稳定输出,光-光效率为69%。激光器单次连续出光时间约30 min,功率稳定性在1%以内。目前激光器输出功率受限于泵浦功率,增加泵浦源的数目有望进一步提高输出功率。     

高效率Nd:YVO4/LBO临界相位匹配脉冲绿光激光器

报道了一种利用激光二极管（LD）端面泵浦Nd:YVO4晶体,声光调Q,LBO临界相位匹配腔内倍频的高效率、小体积、风冷绿光激光器。分析了不同偏振光泵浦的情况下,激光晶体对泵浦光的吸收特性。由分析得出,采用部分偏振光泵浦,可以提高激光晶体对泵浦光吸收均匀性,改善基波畸变,获得高转换效率激光输出。实验中,在泵浦光功率为33 W、声光调Q重复频率为20 kHz时,得到脉宽为23.96 ns、平均功率为15 W的1064 nm基频光输出。经倍频后,得到平均功率为11.2 W的绿光输出,倍频效率为74.6%,总体光-光转换效率为34%。在输出功率为10 W时,测得1 h内输出功率不稳定度为0.512 2%,水平方向和竖直方向的光束质量因子M2分别为1.2和1.1。     

High Power Photonic Crystal Fibre Raman Laser

A cw Raman laser based on a 100-m photonic crystal fibre is demonstrated with up to 3.8 W output power at the incident pump power of 12 W, corresponding to an optical-to-optical efficiency of about 31.6%.. The second order Stokes light, which is firstly reported in a cw photonic crystal fibre Raman laser, is obtained at 1183nm with an output power of 1.6 W and a slope efficiency of about 45.7%.     

Diode-pumped high-power cw blue laser at 473 nm with a compact three-element cavity

We report on a diode-pumped cw Nd:YAG laser operating at 946 nm with a maximum output power of 3.3 W and a slope efficiency of 22% with respect to the incident pump power of 17.5 W. Intracavity frequency doubling with nonlinear crystal LBO yielded a single-ended blue output power of 590 mW with optical conversion efficiency of 3.4%. A very simple, compact three-element cavity of 35 mm long was used. The power fluctuation of the blue laser was 4.3% (rms) at output power level of 400 mW. Transverse mode hopping was observed at higher output power.     

新型全固态激光器作用过程中的激光参数分析

对影响LD泵浦的Nd∶GdVO4,Nd∶YVO4和Nd∶YAG激光器输出特性的增益介质长度、腔内损耗、输出镜透过率、泵浦光和振荡光的光斑大小进行了分析和数值模拟。当腔内固有损耗为2%,输出镜透过率为10%时,Nd∶Gd-VO4,Nd∶YVO4和Nd∶YAG晶体的振荡阈值分别为1.77W、0.55W和3.34W。在25W泵浦功率下,利用1mm长的Nd∶GdVO4,Nd∶YVO4和Nd∶YAG晶体可分别得到13.17W,13.26W和8.43W的输出功率,相应的输出镜最佳透过率分别为24%,44%和16%。     

激光二极管端面抽运的1342nmNd：YVO4激光器

报道了用高功率线列阵光纤耦合激光二极管端面抽运的１３４２ｎｍＤｄ：ＹＶＯ４激光器,在１３．３０Ｗ输入抽运功率下,１３４２ｎｍ激光输出功率达到３．２２Ｗ,斜效率为２５．５％。输出功率不稳定度小于１％。     

Ultimate capacity analysis of cladding-pumped10/130 Tm:fiber laser

The ultimate capacity of a cladding-pumped 10/130 Tm:fiber is experimentally investigated with a 793 nm laser diode bidirectionally pumped amplifier. The laser system works stably at the output powers of 52 W,65 W, and 87 W. Eventually, the damage of the amplifier occurs when the output power reaches about 103.5 W with a total incident pump power of 176.8 W. Considering the incident seed power of 12.3 W,the amplifier conversion efficiency is estimated to be about 51.6% before it is damaged. With valuable exploration, we achieve the first air-cooling 60 W Tm:fiber laser at 1945.845 nm with a spectral linewidth of 0.4 nm.The laser power stability reaches 1.24% during a continuous test time of 65 h. The beam quality is measured as M_x~2=1.16 and M_y~2=1.14.     

LD端面抽运Nd:YAG 1319/1338nm双波长激光器研究

从LD端面抽运固体激光器的激光阈值公式出发,建立了双波长激光同时振荡的阈值条件,理论计算了腔镜对于两个波长的透过率关系,实现了LD端面抽运Nd:YAG 1319nm/1338nm双波长激光连续和准连续输出.双波长激光连续输出功率可达6W,斜效率为30%;准连续输出功率在重复频率50kHz时可达4.75W,斜效率为24.73%,脉冲宽度为55.05ns;腔内插入布儒斯特片,在重复频率为50kHz时,双波长激光准连续线偏振输出功率可达2.22W,不稳定性小于0.52%,M² 关键词： 端泵Nd:YAG激光器 1319nm/1338nm双波长 声光调Q 太赫兹波     

Operation of electro-optically Q-switched Nd:LuAG laser at 1064 nm

We present the operation of a diode-pumped high-power electro-optically Q-switched 4 W Nd:LuAG laser operating at 1064 nm. At an absorbed optical power of 20 W, the laser described provides a maximum output of 3.5 W average power at a repetition rate of 50 Hz. The output varies up to a factor of 1.3% for about 1 h operation with a peak power of 280 kW, with the laser beam quality in the TEM00 mode.     

Efficient Tm:YLF laser with a volume Bragg grating recycle pumped by laser diode

By using a pump recycling configuration, we presented a high efficient diode-pumped Tm:YLF laser with a volume Bragg grating. When the incident pump power was 33.1 W, a maximum output power of 11.1 W at 1907.8 nm with full width at half maximum of 0.6 nm was obtained. The slope efficiency with respect to the incident pump power was 44.8%, and the optical-to-optical efficiency was 33.5%. In addition, the VBG-based Tm:YLF laser was employed as a pumping source of Ho:YAG laser, the maximum output power of 4.7 W with a slope efficiency of 67.0% was obtained, corresponding to Tm-to-Ho conversion efficiency of 51.6%.