时 间：2018年10月16日10:00-11:30

地 点：全讯官网A101

报 告 人：Dmitry V. Churkin教授，俄罗斯国立新西伯利亚大学副校长，光纤激光实验室主任

邀 请 人：舒学文 教授

报告题目（Title）：

中文：光纤激光器中的时空非线性动力学

英文：Spatio-temporal nonlinear dynamic in fibre lasers

报告摘要 (Abstract)：

Usually lasers are thought to be operated in some temporal regime, and their dynamics is characterized in temporal domain. However, the nature is more complicated and fascinating. In the present talk, we will discuss how the laser radiation could be represented in the form of spatio-temporal dynamics, when the intensity varies both over time and longitudinal spatial coordinate. In our work we experimentally show that a laser could be operated in a distinct, albeit complex and dynamic spatio-temporal regime. We will reveal a complex spatio-temporal structure in though-to-be completely stochastic generation, and will show a generation of different bright and dark coherent structures in fibre lasers.

Further on, we will discuss the spatio-frequency dynamics, i.e. the dynamics of the laser’s generation spectrum. We will discuss how the spectral dynamics, i.e. instantaneous spectrum at each cavity round-trip, could be measured in fiber lasers generating different type of radiation, both regular and irregular pulses and quasi-CW radiation by using a combination of heterodyning and intensity spatio-temporal measurement concept. Using this method, we will reveal the existence quasi-stationary localizes lasing modes in the radiation of random fibre laser.

激光通常被认为是在某时间体系内实现运转，且其动力学也是通过时域来进行表征。然而，其本质更加复杂和迷人。在本次报告中，我们将讨论当强度随时间和纵向空间坐标变化时，如何以时空动力学的形式来描述激光辐射。在之前的工作中，我们通过实验证明了激光可以在一个独特、复杂的动态时空体系中实现运转。我们将揭示一个完全随机产生的复杂时空结构，且其将在光纤激光器中生成的一种明暗相干结构。

更进一步，我们将讨论空间频率动力学，即激光器生成的光谱动力学。我们将讨论如何通过结合外差法和强度时空测量思想，来探测光纤激光器中，包括规则和不规则脉冲以及准连续光辐射在内的不同激光辐射类型的光谱动态演化，即腔内往返的瞬时光谱。利用该方法，我们将揭示随机光纤激光器中存在的准静态定位激光模式。

报告人简介 (Biography)：

Dmitry Churkin is a Vice-rector for Research at Novosibirsk State University ranked among 50 best universities world-wide in physics by QS. Previous to this role, he spent 5 years at Aston University, UK, working on nonlinear dynamics in fibre lasers and new types of fibre lasers. He realized the world longest fibre laser measuring 270 km. He contributed massively to the concept and realization of random fibre lasers. He has multiple publications in Nature Photonics, Nature Communications, Physics Reports, Physical Review Letters and other high-impact journals.

Dmitry Churkin教授，新西伯利亚国立大学副校长，光纤激光实验室主任。 2011-2016年，以高级研究员身份工作于于英国阿斯顿大学，从事光纤激光器和新型光纤激光器的非线性动力学研究。他实现了世界上最长的光纤激光器（270公里）并为推动随机光纤激光器的研究作出了实质性贡献。他在欧洲、俄罗斯和中国的大量合作项目中身兼要职，并且在Nature Photonics，Nature Communications，Physics Reports，Physical Review Letters和其他具有高影响力的期刊上发表过多篇论文。