Ultrafast dynamics in complex systems

自从1895年发现x射线以来，人们对物质的结构有了新的认识，这是以前用传统的光学方法无法做到的。在过去的十年中，来自不同科学领域的研究人员正在等待x射线脉冲以高时间分辨率探测动态过程。这一探索激发了x射线自由电子激光设备的建设。除了巨额的初始财政投资（数十亿美元）之外，它们的缺点是可用性有限，限制了可能的实验数量。******因此，对替代超短x射线源的大力开发正在进行。近年来，我的团队利用先进激光光源（ALLS，位于INRS-ÉMT）开发了频域光参量放大器（FOPA），这是一个国际认可的概念。这种独特的桌面激光技术具有产生高亮度飞至阿秒脉冲的潜力，直到软x射线，通过产生强烈的超短太赫兹脉冲来补充电磁频谱的另一个极端。******基于这一最新进展，我的探索研究计划旨在推动超快技术，从太赫兹到软x射线。通过在这么宽的频率范围内组合脉冲，我的目标是拍摄分子和固体动力学的完整电影。在接下来的五年里，我提出了一个雄心勃勃的计划，以解决超快科学和技术的三个主要挑战：******利用频域非线性光学技术，包括FOPA，用于峰值功率红外和中红外激光脉冲，低至单周期脉冲持续时间，并使用它们产生高亮度软x射线，与强超短太赫兹脉冲完全同步。******通过探测大分子的结构和电子动力学，为尚未探索的分子科学领域开发这些独特的资源。特别是，由核心电子电离引发的分子中的超快化学反应将被成像，以获得与放射生物学领域相关的过程的基本理解。******研究先进材料中的超快动力学及其控制。我们将研究如何使用超短高场太赫兹脉冲来精确控制二氧化钒的光学特性，二氧化钒是一种非常有前途的材料，用于开发未来的信息和通信技术设备。******通过这些需要激光工程、物理、化学和材料科学等多学科专业知识的努力，我建议在未来五年内招收足够数量的年轻研究人员，培养10名实习生、2名硕士和8名博士。这些学员将在世界一流的激光设备ALLS进行实验，并将参加各种国家、国际和工业合作。

Since there discovery in 1895, X-rays have led to new insight on the structure of matter, previously inaccessible with conventional optical methods. Over the last decade, researchers from a broad diversity of scientific horizons are awaiting X-ray pulses to probe dynamical processes with high temporal resolution. This quest motivates the construction of X-ray Free Electron Laser facilities. Their drawback besides a huge initial financial investment (billions of dollars) is limited availability, restraining the number of possible experiments. ******Thus, intense development on alternative ultrashort X-ray sources is undertaken. Over the recent years, my team has capitalized on access to the Advanced Laser Light Source (ALLS, located at INRS-ÉMT) to develop the Frequency domain Optical Parametric Amplifier (FOPA), a concept internationally valued. This unique table-top laser technology bears the potential to generate high brightness femto- to attosecond pulses up to the soft X-rays, complemented by the other extreme of the electromagnetic spectrum through the generation of intense ultrashort THz pulses. ******Founded on this recent progress, my Discovery research program aims to push ultrafast technologies, from the THz to the soft X-rays. By combining pulses within this wide range of frequencies, my goal is to shoot complete movies of dynamics in molecules and solids. Over the next five years, I propose an ambitious program to address three major challenges of ultrafast science and technologies:****** To capitalize on Frequency domain Nonlinear Optical Technologies including FOPA for high peak power infrared and mid-infrared laser pulses, down to single-cycle pulse duration, and to use them for generating high brightness soft X-rays, fully synchronized to intense ultrashort THz pulses.****** To exploit these unique sources for yet unexplored fields of molecular science by probing structural and electronic dynamics in large molecules. In particular, ultrafast chemical reactions in molecules, triggered by the ionization of core electrons will be imaged to gain fundamental understanding of processes relevant to the field of radiobiology.****** To investigate ultrafast dynamics and its control in advanced materials. We will study how ultrashort high-field THz pulses can be used to control precisely the optical properties of vanadium dioxide, a highly promising material for the development of future devices for information and communication technologies.******Through these efforts that require multidisciplinary expertise in laser engineering, physics, chemistry, and material science, I propose to enrol a critical mass of young researchers with the training of 10 internships, 2 M.Sc., and 8 Ph.D. students over the next five years. These trainees will perform their experiments at ALLS, a world-class laser facility, and will join various national, international, and industrial collaborations.