标题： 实现高精度三维强场测量——隧穿区域中的低频场电离 显示英文标题

标题： Enabling high-precision 3D strong-field measurements - Ionization with low-frequency fields in the tunneling regime

摘要： 原子或分子的电离呈现出超出我们现有理解的丰富性：最近用低频场研究强场电离时发现了意想不到的动能结构（1, 2）。 然而，对电子动力学的深刻理解是实现阿秒分辨率再碰撞成像（3）、轨道断层扫描（4）、keV相干光源（5），或者产生 zeptosecond 持续时间 X 射线（6）的前提条件。 我们提出了一种方法，能够以前所未有的精度审视强场动力学。 尽管有五阶更高的动量能，我们的方法仍能在阈值以上仅 1 meV 提供高精度测量。 这一成果是通过专门开发的超快中红外光源与反应显微镜相结合实现的。 我们在隧道电离区域（{\gamma }= 0.3）观察电子动力学，并展示了首个三维动量分布，揭示了令人惊讶的新观测结果：接近零动量的电子和低于 eV 的低动量结构，尽管摆动能量高达 95 eV。 显示英文摘要

摘要： Ionization of an atom or molecule presents surprising richness beyond our current understanding: strong-field ionization with low-frequency fields recently revealed unexpected kinetic energy structures (1, 2). A solid grasp on electron dynamics is however pre-requisite for attosecond-resolution recollision imaging (3), orbital tomography (4), for coherent sources of keV light (5), or to produce zeptosecond-duration x-rays (6). We present a methodology that enables scrutinizing strong-field dynamics at an unprecedented level. Our method provides high-precision measurements only 1 meV above the threshold despite 5 orders higher ponderomotive energies. Such feat was realized with a specifically developed ultrafast mid-IR light source in combination with a reaction microscope. We observe electron dynamics in the tunneling regime ({\gamma} = 0.3) and show first 3D momentum distributions demonstrating surprising new observations of near-zero momentum electrons and low momentum structures, below the eV, despite quiver energies of 95 eV.