Pulse dynamics control in passively mode-locked high energy solid state laser oscillators

被动锁模高能固态激光振荡器的脉冲动态控制

• 批准号: 222279330
• 负责人: Professor Dr. Uwe Morgner
• 金额: --
• 依托单位: Institut für Quantenoptik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2012
• 资助国家: 德国
• 起止时间: 2011-12-31 至 2018-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/222279330?language=en
• 关键词: Pulse; dynamics; control; passively; mode

Mode-locked laser oscillators emitting femtosecond pulses with high repetition rates become more and more powerful. Employing state-of-the-art techniques such as thin-disk or slab based schemes, pulse energies in the 10 µJ range have been generated directly from the laser oscillator. At the same time during this development, people realized a substantial increase of pulse duration well beyond the gain bandwidth limitations which at least partially counteracts the high energy again; we refer it here the scaling problem. From the solitary mode-locked laser oscillator employing a semiconductor saturable absorber - which is the most common type - it is well known that two-photon absorption processes in the absorber mirror form the main limiting process. Nevertheless, a convincing concept for overcoming this limitation was not yet demonstrated. This shall be the subject of this proposal: On the base of a concise analysis of the pulse shaping mechanisms an FPGA control concept is investigated and implemented leading to much shorter pulses from high energy oscillators. Surprisingly enough, the scaling problem is also known from chirped-pulse oscillators (CPO) with net positive dispersion where the pulses are chirped all the time during the oscillator roundtrip. Due to the chirp the model of excessive nonlinearity in the absorber cannot be simply adapted to this case. The scaling problem in this parameter range is not yet explored systematically which shall be subject of this project as well. At the end we will gain new fundamental insight into the nonlinear pulse propagation in high energy solid-state laser oscillators, into their limitations, and into the external control of laser dynamics. We will explore concepts to overcome the scaling problem and to generate high-energy pulses much shorter than now which in turn will be of relevance for many applications in physics and beyond.

模式锁定的激光振荡器发出高度重复率的飞秒脉冲变得越来越强大。采用最先进的技术，例如基于薄盘或平板的方案，已直接从激光振荡器中产生了10 µJ范围内的脉冲能量。同时，在这一开发过程中，人们意识到脉搏持续时间大大增加了远远超出增益带宽限制，这至少部分地抵消了高能量。我们在这里引用缩放问题。通过使用半导体饱和吸收器的固体模式锁定激光振荡器（最常见的类型），众所周知，吸收镜中的两光子吸收过程形成了主要限制过程。然而，尚未证明一个令人信服的克服这一限制的概念。这将是该提案的主题：在对脉冲塑形机制的简洁分析的基础上，研究并实施了FPGA控制概念，从而导致高能振荡器的脉冲较短。令人惊讶的是，从净阳性分散体的chireped脉冲振荡器（CPO）中也知道了缩放问题，在振荡器往返过程中，脉冲一直在搅动。由于鸣叫，吸收器中过量非线性的模型不能简单地适应这种情况。该参数范围内的缩放问题尚未系统地探索该项目的主题。最后，我们将获得对高能量固态激光振荡器中非线性脉冲传播的新基本洞察力，并将其局限性进入激光动力学的外部控制。我们将探索概念以克服缩放问题并产生比现在短得多的高能脉冲，这反过来又将其与物理及其他地区的许多应用相关。

项目成果

Low-noise passive harmonically mode-locked Yb:CALCO laser oscillator

• DOI: 10.1109/cleoe-eqec.2017.8086298
• 发表时间: 2017-06
• 期刊: 2017 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)
• 作者: Hauke Bensch;G. Herink;F. Kurtz;U. Morgner