High-Energy Femtosecond Fiber Lasers by Self-Similar Pulse Evolution

来自康奈尔大学的一个研究小组将对一种产生超短脉冲的新方法进行理论和实验研究：自相似脉冲整形。这一机制是值得注意的，因为在激光器内部存在控制波方程的单调演化的渐近解，尽管要求场在每次穿过腔体后自我复制。自相似脉冲的能量比其他方法稳定产生的能量大得多。这项工作的具体目标包括：*发展对锁模激光器的全面理解，在锁模激光器中，脉冲在穿过激光腔时经历巨大变化*自相似光纤激光器的性能优化*展示飞秒光纤激光器，其性能可与固态激光器相比，甚至超过固态激光器的性能。在这个项目中开发的概念将涉及一系列主题，从非线性动力系统的基础科学到商业激光仪器。产生飞秒持续时间光脉冲的光纤激光器具有巨大的潜力，可以将短脉冲光学技术的范围扩展到实际应用中，例如机械加工、疾病诊断和治疗。自相似光纤激光器具有明显的商业潜力。固体激光器的性能也可以通过这一概念得到显著提高。从事这个项目的学生将获得从理论和数值模拟到光纤光学最技术方面的经验。

Intellectual Merit A group from Cornell University will perform theoretical and experimentalstudies of a qualitatively new approach to ultrashort pulse-generation:self-similar pulse shaping. This regime is remarkable becausemonotonically-evolving, asymptotic solutions of the governing wave equationexist inside a laser, despite the requirement that the field reproduceitself after each traversal of the cavity. Self-similar pulses exist withmuch greater energies than can be produced stably by other means.Specific objectives of this work include* the development of complete understanding of a mode-locked laser in whichthe pulse undergoes large changes as it traverses the laser cavity* optimization of the performance of self-similar fiber lasers* the demonstration of femtosecond fiber lasers that offer performancecomparable to, and even exceding, that of solid-state lasers Broader ImpactsThe impact of the proposed research extends well beyond fiber lasers. Theconcepts developed in this project will bear on a range of topics, from thefundamental science of nonlinear dynamical systems to commercial laserinstruments. Fiber lasers that generate femtosecond-duration optical pulses have greatpotential for expanding the range of short-pulse optical techniques intoreal-world applications such as machining, and diagnosis and treatment ofdisease, for example. Self-similar fiber lasers have clear commercialpotential. The performance of solid-state lasers can also be enhancedsubstantially by this concept. The student working on this project will gain experience ranging from theoryand numerical simulations to the most technical aspects of fiber optics.