High-Performance Femtosecond Fiber Lasers Based on New Pulse Evolutions

目的：这个项目的目标是研究在腔内支持新脉冲演化的光纤激光器，并利用所获得的知识来展示具有前所未有的性能的实用仪器。智力优势：智力优势在于对新的非线性波的理解。超快科学领域建立在激光的基础上，形成孤子，孤子是平衡相移和反常群速度色散的脉冲。近几年，在正色散介质中出现了基于非线性增益和损耗的脉冲整形方法。这种方法具有变革性，因为它与二十年来关于光脉冲产生的传统智慧背道而驰。光脉冲在其增益介质中自相似传输的激光器表现出新的现象，如激光器中存在局部非线性吸引。这种自相似的进化为具有极低噪声的激光和产生只包含几个周期光的脉冲的激光开辟了新的途径。更广泛的影响是展示了具有新能力的有用(最终是商用)仪器，用于产生高能、超短光脉冲。这些仪器将扩大超快科学领域，并将为医疗诊所等新领域带来短脉冲能力。学生将获得从理论和数值模拟到光纤技术方面的经验，以及超短光脉冲应用的知识。光纤激光器的研究将与本科生和研究生实验室相结合。参加由4-H赞助的活动将使农村学生接触到科学技术。

Objective: The objectives of this program are to investigate fiber lasers that support new pulse evolutions in their cavities, and to use the knowledge gained to demonstrate practical instruments with unprecedented performance.Intellectual Merit: The intellectual merit is in understanding of new nonlinear waves. The field of ultrafast science has been built on lasers based on formation of solitons, pulses that balance phase shifts with anomalous group-velocity dispersion. In the last few years, pulse-shaping based on nonlinear gain and loss, in normal-dispersion media, has been introduced. This approach is transformative as it counters two decades of conventional wisdom regarding the generation of light pulses. Lasers with self-similar propagation of light pulses in their gain media exhibit new phenomena, such as the existence of local nonlinear attraction in a laser. The self-similar evolution opens new routes to lasers with very low noise and to lasers that generate pulses that contain only a few cycles of light.Broader Impacts: The broader impacts are the demonstration of useful (and eventually commercial) instruments with new capabilities for energetic, ultra-short light pulses. These instruments will expand the field of ultra-fast science and will bring short-pulse capabilities to new arenas such as medical clinics. Students will gain experience ranging from theory and numerical simulations to technical aspects of fiber optics and knowledge of applications of ultra-short light pulses. The research on fiber lasers will be coupled to undergraduate and graduate laboratories. Participation in activities sponsored by 4-H will expose rural students to science and technology.