自由电子激光场中原子分子实验研究进展

Atomic and Molecular Experiments Progress in Free-Electron Laser Field

近年来,超强、超短、超快自由电子激光新技术在世界得到前所未有的发展,已成为探索光与物质相互作用的全新工具。在原子分子领域,短波自由电子激光的应用主要体现在多光子非线性和超快电子原子分子的反应动力学及控制等领域。从简单He原子到复杂化学生物分子、外壳层到内壳层、单光子到多光子、单脉冲到时间分辨的抽运探测、深紫外到硬X射线,能量谱到有时间分辨的动量谱,实验取得了一系列重大突破,让人们在飞秒时间尺度和原子空间尺度下探索操纵量子规律成为可能。本文系统介绍了本领域的最新实验进展,通过几个代表性研究成果,展示短波自由电子激光在电子、原子、分子量子特性研究中的重要突破。

The free-electron lasers （FELs）, a rapid developing technology as a new generation of advanced radiation sources in the last decade, provide ultra-fast, ultra-intense, ultra-short wavelength laser pulses, becoming a robust metrology to explore the forefront of light-matter interactions. In atomic, molecular and optical （AMO） physics, shortwavelength FELs manifest their benefits in exploring multi-photon nonlinear phenomena, observing and controlling reaction dynamics of electrons, atoms and molecules. Experimental advancements from simple helium atom to complex bio-molecules, from outer-shell to inner-shell electrons, from single-photon to multi-photon processes, from single pulse experiments to time-resolved pump-probe approaches, from extreme ultraviolet to hard X-ray regimes, from energy spectra to time-resolved momentum spectra, have successively achieved, all of which are accessible to observe and manipulate quantum world in aspatial scale of atoms and a temporal resolution of femtosecond. The review selects very recent illustrative experimental results in this field and presents the groundbreaking achievements in intriguing quantum behaviors of electrons, atoms and molecules under intense shortwavelength FEL field, demonstrating the fundamental aspects of AMO physics.