发表机构
Max-Planck-Institut für Kernphysik（马克斯·普朗克核物理研究所）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文研究非绝热隧穿电离中的时间延迟，通过一维短程势模型和强场近似解析分析，发现高阶修正的再碰撞通道（复合与进一步电离）对时间延迟有显著贡献，且在强弱场下与重散射通道的主导性发生反转。
AI 中文摘要
在原子隧穿电离过程中，势垒内再碰撞路径尽管振幅极小，但由于其相对于直接电离路径的相位移动，会在可观测的光电子动量分布上留下印记，这一相位移动可被解释为隧穿时间延迟。我们研究了在非绝热区域中该时间延迟如何被修正，在该区域内隧穿势垒在电离过程中动态演化。我们的分析基于一个由强激光脉冲驱动的一维短程势的简单模型，该模型仍可通过强场近似（SFA）进行系统的解析处理。我们展示了高阶SFA修正的重要贡献，该修正描述了包含复合和进一步电离的再碰撞通道，并且是对重散射的补充。而在准静态区域中，对于相对较大的激光场，复合通道在隧穿时间延迟中主导重散射，但在弱场中它们的贡献发生反转。
英文摘要
The under-the-barrier recollision pathway during the tunneling ionization of an atom, despite its minuscule amplitude, leaves its signature on the observable photoelectron momentum distribution due to a phase shift relative to the direct ionization path, that can be interpreted as a tunneling time delay. We investigate how this time delay is modified in the nonadiabatic regime, where the tunneling barrier evolves dynamically during the ionization process. Our analysis is based on a simple model of a one-dimensional short-range potential driven by a strong laser pulse which remains amenable to a systematic analytical treatment with the strong field approximation (SFA). We show a significant contribution of the high-order SFA corrections, which describes the recollision channel with recombination and further ionization, and is additional to the rescattering. Whereas the recombination channel dominates over the rescattering for the tunneling time delay in the quasistatic regime at relatively large laser fields, their contributions are reversed in weak fields.
