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

康奈尔大学的一个研究小组将对一种新的超短脉冲产生方法进行理论和实验研究：自相似脉冲整形。这种状态是值得注意的，因为控制波方程的单调演化的渐近解存在于激光内部，尽管要求在每次穿过腔体后，场都要复制自己。自相似脉冲的能量要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完全理解，其中脉冲在穿过激光腔时经历了巨大的变化*自相似光纤激光器的性能优化*飞秒光纤激光器的演示，提供与固态激光器相当甚至超过的性能更广泛的影响拟议研究的影响远远超出了光纤激光器。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。产生飞秒持续光脉冲的光纤激光器在将短脉冲光学技术扩展到实际应用（例如机械加工、疾病诊断和治疗）方面具有巨大的潜力。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个概念得到极大的提高。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.