中红外可调谐强激光诱导光电子重散射新现象新物理的探索研究

Photoelectron rescattering, related to ionization of atomic and molecular system driven by a strong laser field, is the underlying mechanism of many strong field phenomena, such as, high-order above threshold ionization, multiple electron ionization, coulomb explosion, production of attosecond pulses and molecular tomography, and so on. Recently, the development of optical parametric amplification technology, has make it possible the availability of mid-infrared laser sources (mJ, tens fs, even few-cycle scale, and wavelength-adjustable in the range of 1-5um), which provides one new research frontier in the strong field physics. Such a new technical breakthrough will make important contributions to all branches of the whole strong field physics community... Based on numerical simulations, in combination with the newly-available wavelength-tunable technology, the research project as to the strong electron rescattering and correlation physcis related to strong field ionization phenomena is proposed. The aim is to provide a useful simulation tool for the research on the multi-electron atomic and molecular complex system, and the emphasis is on the distinguishment of the strong Coulomb field effect on the high energetic photoelctron, electron correlation in the non-sequential double or multiple ionization process, angular correlation in the sequential double ionization process, especially the wavelength-dependent effects and phenomena. Such a study will deepen the understanding to the complex dynamics of strong field ionization processes, and provide a physical guide and support for the further experiments.

强激光场驱动原子分子体系电离引发电子重散射是理解若干强场超快现象，如高阶域上电离、多电子电离、库仑爆炸、阿秒脉冲产生及分子层析成像等的物理基础。近年来,飞秒光参量放大技术的发展,为人们提供了毫焦耳量级、数十飞秒乃至周期量级、波长可调谐(1um~5um)的中红外激光光源,从而开辟了强场物理研究的新前沿。这一新的技术突破对于强场物理研究中各个重要分支将产生深远的影响。. 通过数值仿真模拟，结合“波长可调谐”这一全新技术手段，率先开展强场光电离电子重散射关联现象的物理研究，为对多电子原子分子等复杂系统的研究提供有效的仿真模拟工具，重点揭示库仑场对高能电子动力学行为、非顺序双电离多电离中的电子关联和顺序电离电子角分布关联的波长依赖效应，丰富和深化人们对强场光电离中电子的动力学行为的认识，并为下一步实验的开展提供强有力的理论支持。

通过建立、升级和发展相关数值仿真模拟平台，系统开展了强场光电离电子重散射关联现象与超快激光传输等问题的研究并取得系列创新结果。比如，研究了周期量级涡旋激光在少能级量子系统中的传输响应，首次发现了非线性涡旋前驱子的存在并诠释了其产生的根源[[Phys Rev Lett 117,023901(2016)]；提出并验证了延迟可调的阿秒脉冲对的产生新方案[J Opt 18, 095504 (2016)]；研究了中红外激光驱动下的分子高次谐波譜平台区强度下降现象，揭示其根源为双中心干涉相消，并详细研究了下降位置的载波包络相位依赖规律［Opt Express,23,23834 (2015)]；众多研究内容的开展及所取得的重要结果，可极大地丰富和深化人们对强场光电离和光传输的认识，并为下一步实验的开展提供强有力的理论指导和支持。截至目前已发表３０余篇论文并多次在“强场超快激光物理”等领域内著名的国际会议上做报告，特别是在超快涡旋光物理方面的工作，被人评价为“开创了前驱子和高阶涡旋谐波研究的新领域，为在理解光与物质相互作用方面取得重大进展铺平了道路。