超强超短OPCPA激光系统新型种子源的研究
文献类型：学位论文
| 作者 | 杜鹃 |
| 学位类别 | 博士 |
| 答辩日期 | 2007 |
| 授予单位 | 中国科学院上海光学精密机械研究所 |
| 导师 | 徐至展 |
| 关键词 | 超强超短脉冲激光 光学参量啁啾脉冲放大 LD泵浦 全固态掺Yb晶体激光器 |
| 其他题名 | Research on Development of the Novel Seed Source Used in OPCPA-Based Laser System |
| 中文摘要 | 超强超短激光的发展，为众多科学领域提供了全新的实验手段和极端的物理条件。光学参量啁啾脉冲放大(OPCPA)是近年提出的持续发展台式化超强超短激光系统的新技术途径，其中，种子源的选取对整个OPCPA激光系统输出脉冲的能量、脉宽、稳定性等性能起着重要的作用。目前，OPCPA系统中应用最广的种子光是钛宝石自锁模飞秒激光器或者Nd:glass 振荡器提供的飞秒脉冲。但是当波长处于1um附近时，已经接近钛宝石增益谱的边缘，增益很低；而且，此时一般只有40nm的光谱宽度输出，脉冲宽度减小的潜力有限；另外，在钛宝石的吸收波段，目前还没有相应的激光二极管(LD)泵浦源，一般采用LD对掺钕离子激光器泵浦，再利用其倍频输出对钛宝石激光器泵浦，实现过程复杂，成本较高。而Nd:glass激光器，则由于其增益带宽的限制(<30nm)，只能输出几百飞秒的激光脉冲。因此，迫切需要研究基于新型激光增益材料的种子源。 本论文工作主要是开展了OPCPA激光系统新型种子源研制的理论和实验研究。根据新型掺Yb激光晶体独特的优点，对一系列新型掺Yb的全固态激光器进行了理论分析和创新性的实验研究，验证了掺Yb晶体激光器，尤其是Yb:GYSO和Yb:LYSO激光器，实现宽带可调谐、稳定的飞秒激光输出的优势和最终将掺Yb晶体飞秒锁模激光器作为新型种子源应用到OPCPA系统中的可行性。研究内容包括：对Na,Yb:CaF2晶体锁模特性进行实验研究；对Yb:LSO、Yb:GSO、Yb:GYSO和Yb:LYSO晶体激光器的连续运转特性和波长调谐特性进行了实验研究。主要的创新成果概括如下： 1. 从半导体可饱和吸收镜(SESAM)被动锁模的基本原理出发，结合对Na,Yb:CaF2晶体各项激光性能参数的分析，首次对Na,Yb:CaF2激光器进行了被动锁模激光输出特性的实验研究。实验结果表明，Na,Yb:CaF2激光器在实现超短脉冲和高峰值功率输出方面，具有非常显著的优点。 2. 采用波长978nm 的LD作为泵浦源，对5at.% Yb:LSO晶体的激光特性进行了实验研究，得到了Yb:LSO激光器波长为1082nm的输出，对应的斜效率为55%。对于中心波长为1061nm的激光运转，得到了3.1W的最佳输出，光-光转换效率55.4%，对应的斜效率为64.7%。在波长调谐的实验中，分别获得了调谐带宽为59nm和64nm 的宽带调谐激光输出。 3. 在对5at.%与10at.% Yb:GSO晶体激光特性进行分析的基础上，采用不同的腔镜，分别对两种晶体在不同波长下的激光运转特性进行了实验研究。5at.% Yb:GSO激光器运转在1089nm时激光运转的斜效率高达71.2%，表现出非常优异的激光性能。在腔内插入一SF10棱镜进行波长调谐的实验，最终得到了调谐带宽范围达65nm的宽带波长调谐。 4. 首次对5at.%Yb:G0.5Y0.5SO晶体激光器的连续波运转输出特性和波长调谐性能进行探索性实验研究，并对Yb:GYSO激光器进行了被动锁模初步实验。连续激光器输出波长1081.5nm，对应的斜效率为57%。在波长调谐实验中，我们得到了59nm的调谐范围，而且其调谐曲线与Yb:GSO激光器相比，更加平坦、光滑，有利于实现超短脉冲输出。同时还获得426mW、重复频率为168MHz的连续锁模脉冲输出。这些实验结果证明Yb:GYSO激光器不但保留了Yb:GSO激光器优异的激光特性，同时还具有YSO晶体良好的晶体性能，无论在高功率连续激光器运转还是超短脉冲激光输出方面，都非常具有应用前景。 5. 对5at.%Yb:LYSO连续运转激光器进行了波长调谐实验研究时，分别得到了从1030nm 到1111nm和 1004nm到1090nm的宽调谐激光输出，调谐带宽分别为81nm和86nm，这是据我们所知从Yb:LYSO激光器获得的最宽的波长调谐范围。实验证明，Yb:LYSO 混晶充分结合了Yb:LSO激光器优异的输出性能和Yb:YSO晶体易于生长、成本低廉的优点，并且相对于两种单晶，具有更宽的调谐特性，从而更加适合用飞秒锁模脉冲激光器的增益介质。并且，我们对Yb:LYSO飞秒被动锁模激光器进行了初步的实验研究。 在攻读博士学位期间，本人与他人合作在国内外学术刊物上发表的与本研究项目有关的论文7篇，其中第一作者3篇；在国内外学术会议上发表论文4篇，第一作者2篇；与他人合作申请发明专利1项。 |
| 英文摘要 | With the development of ultra-intense and ultra-short laser system, unprecedented experimental instruments and extreme physical research condition have become reality. Especially, optical parametric chirped pulse amplification (OPCPA), which combines optical pulse amplification (OPA) with chirped pulse amplification (CPA), is a new technical approach for the development of the table-top ultra-intense and ultra-short laser presented in recent years. It is well known that proper selection of the seed source is one of the most important factors that influence the output energy, pulsewidth, and stability of the ultra-intense and ultra-short laser system. Currently, the most widely used seed pulses are from Kerr-lens mode-locked Ti:sapphire lasers. However, laser wavelength longer than 1um is near the edge of the gain spectrum of Ti:sapphire, high pump power is needed to achieve stable mode-locked laser pulses and the pulse duration is limited by the gain bandwidth. In addition, Ti:sapphire lasers can not be directly pumped by LD. Normally, the pump source is the frequency-doubling of LD-pumped Nd:YAG or Nd:YVO4 laser. The whole process is very complicated and highly costly, so it is imperative for the appearance of more feasible and compact seed source. In this dissertation, we focused on the theoretical and experimental research on series of novel Yb-doped lasers and their feasible amplification as novel seed source in our OPCPA system. Firstly, novel LD pumped Na,Yb:CaF2 passive mode-locked laser has been reported for the first time to the best of our knowledge. Secondly, two Yb-doped lasers, namely Yb:LSO and Yb:GSO was developed, and high conversion efficiencies and broad tunable wavelength range have been achieved. Afterwards, we experimentally investigated the laser performances of two mixed laser crystals, Yb:GYSO and Yb:LYSO. Favorable laser performances such as high conversion efficiency and broad wavelength tuning have been exhibited, which suggest that Yb:GYSO and Yb:LYSO lasers are very suitable to be used for a mode locked laser operation, which can be further employed as novel seed sources in OPCPA system. The main results are summarized as follows: 1. Based on the principle of passively mode locking by SESAM, we have demonstrated the passively mode-locked laser performance of the Na,Yb:CaF2 laser for what is to our knowledge the first time. We obtained transform-limited 1-ps passively mode-locked laser pulses under the self-Q-switched envelope. Experimental results convince that the novel Na,Yb:CaF2 laser is promising for achieving ultra-short and high peak power pulses. 2. Using a LD emitting at 978nm, we investigated the laser performance of 5at.% Yb:LSO crystal. Laser operation at 1082nm was achieved for the first time as we know, and its slope efficiency reached 55%. Also, we experimentally investigated its tunable ability, and broad tunable wavelength ranges of 1028nm to 1087nm and 1022nm to1086nm were obtained. 3. Using two different series of coating cavity mirrors, 5at.% and 10at.% Yb:GSO lasers have been demonstrated. Especially, 5at.% Yb:GSO laser exhibited excellent performance at 1089nm, and its laser slope efficiency arrived at 71.2%. By inserting an SF10 dispersive prism, we achieved a broad continuous wavelength tunable range of 65nm, from 1028nm to 1093nm. 4. For what is to our knowledge the first time, laser operation of Yb:GYSO laser was investigated. High conversion efficiency and broad tunable wavelength range have been achieved, and its tunable range is smoother than that of Yb:GSO laser. Also, we have done some tentative experiments on the mode-locked Yb:GYSO laser. Experimental results indicate that Yb:GYSO laser integrated the high laser performance of Yb:GSO and good mechanical properties of Yb:YSO simultaneously, and it is one of the most excellent lasers for achieving high-power diode-pumped cw and femtosecond lasers. 5. To our knowledge, the broadest wavelength tunable curves achieved from Yb:LYSO laser have been demonstrated, which are from 1030nm to 1111nm and from 1004nm to 1090nm, respectively. Yb:LYSO retains excellent laser properties of LSO with reduced growth cost, as well as the favorable growth properties of YSO. Owing to its broad and flat wavelength tuning range, it is also favorable to be used for a mode locked laser operation. We also experimentally investigated the femotosecond mode-locked Yb:LYSO laser preparatorily. In consequence, although the research is still primary, Yb:LYSO offers an promising alternative for achieving efficient, low-cost, high-power diode-pumped broadly tunable cw or mode locked lasers. |
| 语种 | 中文 |
| 源URL | [http://ir.siom.ac.cn/handle/181231/15560]  |
| 专题 | 上海光学精密机械研究所_学位论文 |
| 推荐引用方式 GB/T 7714 | 杜鹃. 超强超短OPCPA激光系统新型种子源的研究[D]. 中国科学院上海光学精密机械研究所. 2007. |
入库方式： OAI收割
来源：上海光学精密机械研究所
浏览0
下载0
收藏0
其他版本
除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。