Dark blue erenkov second harmonic generation in the two-layer-stacked hexagonal periodically poled MgO:LiNbO_3s

We report the dark blue nonlinearˇCerenkov radiation by the second harmonic generation(SHG)in a two-layer-stacked hexagonal periodically-poled-MgO:LiNbO3s(PPMgOLNs).Based on the direct wafer bonding of two target PPMgOLNs rotating around the axis perpendicular to the plane with an angle of 30°,twelve bright spots as twice of those in a single PPMgOLN are shown at each second-harmonicˇCerenkov ring.The experimental results agree with the theoretical ones and present a promising application in the fabrication of three-dimensional(3D)PPMgOLNs.     

A 45-μJ, 10-kHz,burst-mode picosecond optical parametric oscillator synchronously pumped at a second harmonic cavity

A novel high-energy picosecond optical parametric oscillator (OPO) was realized by placing an OPO in a second-harmonic (SH) cavity. In a proof-of-principle experiment, we demonstrated excellent burst energy of 45 μJ for the OPO signal at 900 nm that operates at a pulse repetition rate of 10 kHz and a pulse width of 46.8 ps. The beam quality was measured as $M^{2}_{x} = 1.44$ and $M^{2}_{y} = 1.40$ in the orthogonal directions, corresponding to an average beam factor $M^{2} = 1.42$. So far, this study is the first to investigate high-energy ps OPO synchronously pumped in a second-harmonic cavity.     

国产Nd:YAG透明陶瓷实现10.0 W激光输出

最近,中国科学院物理研究所、中国科学院上海硅酸盐研究所和中国科学院理化技术研究所合作,获得了较高质量的Nd∶YAG多晶陶瓷并实现了热容运转10.0W的激光输出。实验中使用的Nd∶YAG多晶陶瓷Nd3 掺杂原子数分数为1%,尺寸为3.5mm×3.5mm×12mm。图1给出了Nd∶YAG陶瓷在700～1200nm间的透射率曲线,在1064nm处的透射率为87.0%。用α代表损耗系数,则exp(-αl)=87.0%,其中l表示陶瓷的长度。因此损耗系数α=0.116cm-1。开展了Nd∶YAG陶瓷的热容运转激光性能研究,即在激光工作过程中激光介质处于绝热状态。实验装置如图2所示,激光陶瓷由两…     

脉冲激光的非相干合成技术研究

为了实现高功率、高光束质量的激光输出,采用脉冲激光同步延时控制技术,将多束脉冲激光按时序合成一束脉冲激光,可用于产生大功率激光源。利用所设计的激光脉冲同步延时控制器,控制各个激光脉冲的时序,使按时序输出的多路激光脉冲依次通过光束合成装置,在空间合成为一束。在实验中将3束脉冲激光束合成,合成效率达到95.8%。结果表明,合束后的脉冲激光功率基本等于各束光相加的总和,同时保持了较好的光束质量。     

High-energy picosecond single-pass multi-stage optical parametric generator and amplifier

We demonstrate a new management of multi-stage optical parametric generator(OPG)and amplifier(OPA)to obtain high-energy picosecond sources with high beam quality.The setup of multi-stage OPG-OPA requires mode-matching between the pump beam and the stable mode of the OPG-OPA.In a proof-of-principle experiment,the single-pass multi-stage OPG-OPA consists of three walk-off compensated KTP crystal pairs and two lenses,pumped by an 86 ps,1064 nm 10 kHz picosecond laser.The signal light at~1.77μm has an average output power of 502 mW with record energy up to 50.2μJ.The beam quality factor of the signal light can be improved toM²_x ×M²_yafter filtering out about 40%signal power.To the best of our knowledge,it is the first picosecond single-pass multi-stage OPG-OPA pumped at kHz regime.     

A 117-W 1.66-Times Diffraction Limited Continuous-Wave Nd:YVO_4 Zigzag Slab Laser with Multilayer Amplified-Spontaneous-Emission Absorbing Coatings

We report a continuous-wave end-pumped Nd:YVη₄ zigzag slab laser with multilayer amplified spontaneous emission(ASE) absorbing coatings.The coatings are deposited on the slab faces.A five-layer structure consists of SiO₂-Ti-SiO₂-Ti-Au,and the thicknesses are 2520 nm,10 nm,160 nm,24 nm and 200 nm,respectively.The designed coatings show good performance for the ASE control in the experimental tests.A stable-unstable hybrid laser oscillator along orthogonal directio...     

碱金属蒸气激光器的研究进展

碱金属蒸气激光器具有高量子效率且易于流动散热,显示出良好的发展潜力。概述了光抽运碱金属蒸气激光器的基本原理和国内外的研究进展。对于其在发展中遇到的问题进行了简要分析,并总结了目前所采用的相应解决方案,指出了几种方案所存在的优、缺点。对碱金属蒸气激光器未来可能的研究方向进行了展望。     

高功率深紫外177.3 nm激光倍频产生

全固态深紫外激光器在光刻和高分辨光谱仪等领域有重要应用价值,而非线性光学晶体KBBF及棱镜耦合技术的应用实现了直接倍频产生深紫外激光(λ<200 nm),为全固态深紫外激光器实用化开辟了新途径.2003年,我们与日本东京大学合作,用该方法产生深紫外177.3 nm激光的输出功率为3.5 m     

171 W,1.3 μm调Q准连续全固态激光器

1.3μm全固态激光及其倍频660 nm激光在医疗、显示、娱乐、科研等领域有着非常重要的应用价值。据报道,当前1.3μm全固态激光输出功率为122 W(连续波)。中国科学院物理研究所许家林等采用自行研制的大功率连续抽运激光头,通过热近非稳区谐振腔优化设计和调Q技术相结合,并利用Nd的4F3/2→4I13/2跃迁辐射获得了1.3μm准连续激光输出,平均功率171 W,光-光效率19%,脉冲宽度171 ns,运转频率5 kHz。实验装置如图1所示,每个激光头抽运功率为600 W,激光头中所用的Nd∶YAG激光晶体尺寸为5 mm×100 mm,掺杂原子数分数为0.6%;在两个相同的激光头…