986 resultados para Cr : YAG


Relevância:

20.00% 20.00%

Publicador:

Resumo:

制备了高质量的Yb:YAG透明陶瓷.Yb:YAG透明陶瓷的晶粒尺寸为10μm左右且分布均匀,晶界处和晶粒中没有杂质、气孔的存在.Yb:YAG样品中所有元素分布均匀,不同的晶粒间,晶粒和晶界间成分是一致的,没有出现成分的偏析.4mm厚样品的透过率为80%.LD泵浦获得了波长为1030nm,最大功率为268mW的连续激光输出.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

用温度梯度法生长了直径为75mm大尺寸的Nd:YAG激光晶体,通过退火排除了生长过程中进入晶体的碳原子.用正交偏光显微镜观察了晶体的核心分布以及生长条纹.测试了室温下的吸收谱并利用吸收谱研究了Nd离子在YAG晶体中的分布.比较了温度梯度法与提拉法生长晶体的区别.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

YAG单晶是高功率激光的重要材料,近年来高透明度多晶陶瓷作为激光介质引起人们广泛的注意。YAG陶瓷相对单晶具有易制造大尺寸、掺杂浓度高、易批量生产等优点。在Nd:YAG陶瓷获得长足发展的同时,Yb掺杂的陶瓷也得到了越来越多的关注。Yb:YAG陶瓷与Nd:YAG陶瓷相比具有许多优点:Yb掺杂的激光介质无交叉弛豫振荡和激发态吸收,有较宽的吸收带,较长的荧光寿命及较高的量子效率等。因此,高质量的Yb:YAG陶瓷将是非常理想的高功率激光材料。

Relevância:

20.00% 20.00%

Publicador:

Resumo:

利用浮区法生长得到β-Ga2O3:Cr单晶体.在室温下测试了β-Ga2O3:Cr单晶体的吸收光谱和发射光谱.通过吸收光谱计算了晶体场分裂系数Dq和Racah系数,得到10Dq/B=23.14,表明Cr^3+在β-Ga2O3晶体中处于较弱的晶体场β-Ga2O3:Cr单晶体经高温退火后Cr^3+的发射明显加强,而绿光的发射减弱.采用420nm波长激发,在691nm可得到强而宽的特征发射,此发射对应于Cr^3+的^4T2→^4A2跃迁.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

应用中频感应提拉法生长出掺杂浓度为10 at.-%的Yb:YAG与Yb:YAP晶体,对比了室温下两种晶体的吸收和发射光谱特性。结果表明,Yb:YAG晶体比Yb:YAP晶体有更好的激光性能和低的阈值;同时对比发现,Yb:YAP晶体的吸收截面是Yb:YAG晶体的2.16倍,它容易实现LD泵;由于Yb:YAP晶体的各向异性,它有轴向效应明显,它可以产生偏振激光。

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Single-frequency output power of 7.3 W at 2.09 mu m from a monolithic Ho:YAG nonplanar ring oscillator (NPRO) is demonstrated. Resonantly pumped by a Tm-doped fiber laser at 1.91 mu m, the Ho:YAG NPRO produces 71% of slope efficiency with respect to absorbed pump power and nearly diffraction-limited output with a beam quality parameter of M-2 approximate to 1.1. (c) 2008 Optical Society of America

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The YAG crystal codoped with Yb3+ and Tm3+ has been grown by Czochralski (Cz) method. The crystal structure of the crystal has been determined by X-ray diffraction analysis. The absorption and emission spectra of Yb,Tm:YAG crystal at room temperature have also been studied. The emission cross-sections have been calculated by Fuechtbauer-Ladenburg formula and reciprocity method. (C) 2007 Elsevier B.V. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Optical properties and microstructure of Ag film on glass substrate with Cr intermediate layer were studied by using spectrophotometer and XRD. The spectra results showed that introducing Cr intermediate layer reduced the surface roughness and promoted the reflectivity of Ag film. The XRD analysis showed that the crystalline grains increased and the stress decreased. The adhesion was also improved by using the tape test method. (c) 2006 Published by Elsevier B.V.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The single- and multi-shot damage behaviors of HfO2/SiO2 high-reflecting (HR) coatings under Nd:YAG laser exposure were investigated. Fundamental aspects of multi-shot laser damage, such as the instability due to pulse-to-pulse accumulation of absorption defect and structural defect effect, and the mechanism of laser induced defect generation, are considered. It was found in multi-shot damage, the main factors influencing laser-induced damage threshold (LIDT) are accumulation of irreversible changes of structural defects and thermal stress that induced by thermal density fluctuations.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

作为微电子和光电子系统中普遍使用的一种结构材料,单晶硅一直是人们研究的焦点。长期以来,人们对其电学性质进行了非常深入细致的研究,却疏于对其抗击强激光辐照特性的研究。随着激光通讯和光电对抗技术的发展,对光学材料的激光破坏特性和加固技术进行研究的需求也显得越来越迫切。本文主要对单晶硅的抗激光损伤特性进行研究,研究了单晶硅材料在1064nmNd:YAG激光自由脉冲输出模式和单脉冲输出模式作用下的损伤特性,通过对两种激光作用下单晶硅损伤形貌的分析,在热效应与热力耦合模型的基础上,对单晶硅的激光损伤机制进行了探索。

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The laser-induced damage (LID) behavior of narrow-band interference filters was investigated with a Nd:YAG laser at 1064 nm under single-pulse mode and free-running mode. The absorption measurement of such coatings was performed with surface thermal lensing (STL) technique. The damage morphologies under the two different laser modes were also studied in detail. It was found that all the filters exhibited a pass-band-center-dependent absorption and laser-induced damage threshold (LIDT) behavior, but the damage morphologies were diverse. The explanation was given with the analysis of the electric field distribution and the operational behavior of the irradiation laser. (c) 2005 Elsevier B.V. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

以1030nm高反.940。980nm高透的波长分离膜作为实例,为提高该薄膜元件的波长分离效果,从膜系的优化方面做了一系列的研究。诸如采用带通滤光片的设计思想,在膜堆两侧加入了匹配层,调整膜堆的周期厚度,并用膜系设计软件对通带作进一步的优化。通过这一系列的优化设计后.利用RF双离子柬溅射工艺在BK7玻璃基底上沉积样品薄膜,并在基底背面加镀通带增透膜。结果显示,透射带在940和980nm处的透过率分别为97.73%和93.63%.反射带在1030nm的反射率为99.99%。对所制备的样品薄膜进行了激光损伤阈

Relevância:

20.00% 20.00%

Publicador:

Resumo:

研究了在玻璃基底上镀制Al2O3和Cr过渡层对Ag膜反射率及附着力的影响.分光光度计测试了Ag膜的反射率,结果表明,与Cr过渡层相比,Al2O3过渡层对Ag膜反射率的降低相对较小;而且,随着Al2O3厚度的增加,Ag膜的反射率先增大后减小.XRD与AES测试表明,引入Al2O3或Cr可明显细化Ag晶粒,减弱Ag膜(111)织构;Al2O3作过渡层时,Al原子向Ag层中扩散显著;而Cr作过渡层时,只有少量Cr原子扩散进入Ag层.因此,Al2O3作过渡层能显著增强薄膜与玻璃基体之间的附着力.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

采用计算模拟的方法.研究了光栅式扫描预处理的扫描方式以及脉冲能量波动、定位误差对预处理效率的影响。研究发现。脉冲能量波动及其定位误差使预处理效率降低,同时其影响与扫描方式之间存在相互调制作用.因此可以通过选择合适的扫描方式以及扫描间隔来优化预处理流程,提高预处理效率。此外发现,光斑呈等边三角形排列时的预处理效率优于正方形。