近日，华东师范大学的倪宏程及其研究团队取得一项新进展。经过不懈努力，他们实现强场电离中亚周期非绝热-非偶极耦合的可视化。相关研究成果已于2024年12月16日在国际知名学术期刊《物理评论A》上发表。

本研究提出了两种实验上可行的方案，用于直接可视化非绝热效应和非偶极隧穿效应之间的亚周期相互作用。这两种方案的关键在于，释放的光电子在特定光发射角下所转移的平均线性动量的交点，该交点的大小可作为耦合强度的指标。

此外，通过定义激光场的瞬时有效角频率，研究人员推导出能够定量描述耦合效应的解析表达式。这项研究结果提供了一种清晰直观的方法，来可视化亚周期非绝热-非偶极耦合效应的影响，从而增强了他们对光通过隧穿过程向电子同时传递能量和线性动量的时间分辨过程的理解。

据悉，光-物质的相互作用涉及能量和线性动量向物质的转移。在强场隧穿电离的背景下，这种转移分别表现为非绝热效应和非偶极效应，并且已被证明在亚周期尺度上存在相互作用。

附：英文原文

Title: Visualization of subcycle nonadiabatic-nondipole coupling in strong-field ionization

Author: Xiaodan Mao, Hongcheng Ni, Jian Wu

Issue&Volume: 2024/12/16

Abstract: Light-matter interaction involves the transfer of both energy and linear momentum to matter. In the context of strong-field tunneling ionization, they are manifested as nonadiabatic and nondipole effects, respectively, which have been shown to interact on the subcycle scale. In this work we propose two experimentally feasible protocols for direct visualization of the subcycle interplay between nonadiabatic and nondipole tunneling effects. These protocols hinge on the intersection of the average linear momentum transferred to the released photoelectron at a specific photoemission angle, with the magnitude of this intersection serving as an indicator of the coupling strength. In addition, by defining the instantaneous effective angular frequency of the laser field, we have formulated analytical expressions that provide a quantitative description of the coupling effect. Our results provide a clear and intuitive approach to visualizing the impact of the subcycle nonadiabatic-nondipole coupling effects, thereby enhancing our comprehension of the time-resolved tunneling process through which light imparts both energy and linear momentum to electrons.

DOI: 10.1103/PhysRevA.110.063113

Source: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.110.063113