Ultrafast dynamics in complex systems

复杂系统中的超快动力学

• 批准号: RGPIN-2017-06187
• 负责人: Legare, Francois
• 金额: $ 3.35万
• 依托单位: Institut national de la recherche scientifique
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=712078
• 关键词: Ultrafast; dynamics; complex; systems

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.

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。