强场分子物理中多电子效应

Multielectron effects in the interaction between strong-laser fields and molecules are one of the key point for deeply understanding and solving problems in strong-field molecular physics, and also play an important role in new attosecond science. The advanced experimental techniques and accurate theoretical calculation methods that are developed recently have opened a brand-new opportunity for further insight investigating such important effect. The present proposal will focus on the multielectron effect in strong field molecular physics. We will develop robust experimental techniques and theoretical methods, including the CEP stabilization and the phase/waveform modulation technique for real-time measurements, the combined technique for accurate orientation of molecules in free-space and coincident measurement of 3-dimension momentum of charged particles, and the time-dependent calculation and simulation methods for dealing with the multielectron effects in strong-field molecular physics. With the combination of these techniques and methods, we will carry out complete studies on various molecular multielectron effects in the dynamics both for ionizing electrons and rescattering electrons that are driven by the ultra-short pulsed strong laser fields. The purpose of the proposal is to achieve more knowledge on the molecular multielectron effects, thus to reveal the underlying mechanism and physical properties which control such important effect in strong-field molecular physics. The aims of the proposed studies is to develop the elaborate techniques and methods, to promote our understanding on the underlying physics, for multielectron effect in strong laser interaction with molecules, and to provide essential supports that can be utilized in the prospective research fields such as real-time measurement of molecular structure, ultrafast tomography of molecular orbitals, and so on.

强激光场与分子相互作用中的多电子效应，是进一步的认识深化和解决强场分子物理问题的关键之一，对于发展崭新的阿秒科学也是非常有意义的。新近发展的一些先进实验方法和精确理论计算为认识这一重要效应提供了新机遇。项目以强场分子物理中的多电子效应为研究重点，通过建立载波包络相位及剪裁超快光场的波形和相位实时测量方法、结合自由空间分子精确取向技术和荷电粒子动量符合成像方法的实验装置、适用于多电子问题含时的分子强场理论计算及模拟方法，系统研究强激光场与分子相互作用产生电离的电子动力学过程及其相关现象，旨在获取和深入理解分子强场电离相关的电子动力学和电离电子回撞动力学中多电子效应的物理图像，揭示超快强光场与分子相互作用中新物理机制和规律。项目研究将有力的促进强激光场与分子相互作用的认识，为超快分子结构测定、分子轨道形貌成像等具有前瞻性的强场分子物理应用提供急需的支持。

强激光场与分子相互作用中的多电子效应，是进一步的认识深化和解决强场分子物理问题的关键之一，对于发展崭新的阿秒科学和超快分子成像技术也具有重要意义。本项目以强场分子物理中的多电子效应为研究重点，开展强激光场与分子相互作用产生电离的电子动力学及其相关现象，包括超快光场中分子的激发、电离/解离及各种电子回撞动力学过程等前沿问题研究，获得的主要研究成果包括：（1）发展了超快强激光场调制、分子准直取向操控以及离子-电子多体符合测量技术，实现了分子坐标下强场动力学过程的测量和多粒子动量符合成像测量，具备了亚光学周期下强场多粒子运动学完全测量的实验能力。（2）发现了分子强场电离相关过程中多电子态相干干涉、内层轨道电离诱导解离和质子转移、轨道干涉效应等多电子及多轨道效应，获取了强场激发及亚周期的ac-Stark效应等新现象及其规律，确认了不同分子轨道结构以及亚周期的电子响应对电离解离过程的影响。（3）通过对多电子过程在电离电子回撞分子动力学中影响的细致分析和精确操控，发现并证实了分子体系中电子回撞产生Rydberg激发的普遍存在及其量子干涉效应，提出了隧穿电子伴随阈上电离的相干俘获机制；揭示了电子回碰动力学在分子多次电离中的重要作用和不同轨道结构对电离解离的影响。（4）基于强激光诱导的多次电离分子或分子团簇库仑爆炸成像，开拓了在多原子分子结构测量和弱束缚分子团簇结构超快成像方面的应用，获得了C6H6分子高精度结构、OCS和N2O分子二聚体团簇及其同分异构体三维结构成像，并通过测量电荷分布对库仑场近似修正，成功地对C6H6二聚体、三聚体的核间距进行了亚埃量级的测量。这些研究成果深入地理解分子强场电离相关的电子动力学和电离电子回撞动力学中多电子效应的物理图像，揭示超快强光场与分子相互作用中新物理机制和规律，并推动其在相关领域的应用。