强XUV光下原子分子电离过程的研究进展(特邀)  

Photoionization of Atoms and Molecules by Strong XUV Pulses(Invited)

作　　者：刘光殷 姜维超 彭良友[2] Liu Guangyin;Jiang Weichao;Peng Liangyou(Institute for Quantum Precision Measurement,College of Physics and Optoelectronic Engineering,Shenzhen University,Shenzhen 518060,Guangdong,China;State Key Laboratory of Artificial Microstructure and Mesoscopic Physics,School of Physics,Peking University,Beijing 100871,China)

机构地区：[1]深圳大学物理与光电工程学院量子精密测量研究所,广东深圳518060 [2]北京大学物理学院人工微结构和介观物理国家重点实验室,北京100871

出　　处：《光学学报》2024年第17期2-19,共18页Acta Optica Sinica

基　　金：国家自然科学基金(12074265,12234002,92250303);广东省基础与应用基础研究基金(2022A1515010329)。

摘　　要：随着近年来自由电子激光技术的发展,强极紫外(XUV)激光脉冲作用下的原子分子电离过程逐渐成为强场物理领域的研究热点之一。强XUV光下的电离过程中存在很多新奇,甚至反直觉的非微扰效应。主要介绍近年来在XUV光下的原子稳定化、Autler-Townes(AT)分裂和动态干涉上的研究进展。主要涉及原子稳定化出现的机制及探测方法,原子稳定化区域光电子角分布的变化,拉比振荡与AT分裂的联系,AT分裂的峰间距、相对峰高、双峰之间的次峰结构,阈上和阈下电离过程中动态干涉出现的条件,单电离与双电离能谱中的动态干涉构型,动态干涉与原子稳定化的联系,动态干涉与AT分裂之间的联系,以及非偶极修正与电子关联的影响等。Significance With the rapid development of free-electron laser(FEL)sources,the ionization of atoms and molecules by strong extreme ultraviolet(XUV)pulses has become a major topic in strong-field physics.A range of novel and even counterintuitive non-perturbative phenomena can be observed in photoionization with strong XUV pulses.This review focuses on non-perturbative effects in photoionization processes,including atomic stabilization,Autler-Townes(AT)splitting,and dynamic interference.Progress At high laser intensities,instead of being ionized,the electron tends to remain bound near the nucleus.This suppression of ionization in the high-frequency and high-intensity regime is often referred to as atomic stabilization.In the Kramers-Henneberger(KH)frame,the atomic bound electron wave function evolves into a dichotomous state at high laser intensity,leading to a reduced ionization rate.The formation of dichotomic KH states suggests that stabilization can be monitored by the angle-resolved spectra of the photoelectron.Molecule-like two-center interference fringes are predicted to be observable in a pump-probe scheme.Experimentally,atomic stabilization can be interpreted as the temporal destructive interference of photoelectrons ejected at different times.The angular distribution of the photoelectron in the stabilization regime differs significantly from that in the perturbative regime.Early studies based on reduced-dimensional time-dependent Schrödinger equation(TDSE)calculations suggest that stabilization can be disrupted by nondipole effects or electron-correlation effects.More recent full-dimensional TDSE calculations show that nondipole corrections can even enhance stabilization if a suitable pulse duration is chosen.When the photon energy matches the energy difference between two bound states,Rabi oscillations of the populations can be induced in a two-level system.Rabi oscillations have been identified in a variety of physical systems,including ultracold atoms,Rydberg atoms,molecules,metal nanostructures,Jose

关 键 词：超快光学 强场电离 原子稳定化 Autler-Townes分裂 动态干涉 

分 类 号：O562.4[理学—原子与分子物理]