近日，瑞士苏黎世联邦理工学院Hans Jakob Wörner团队研究了手性光电离动力学的阿秒控制与测量。2025年8月27日出版的《自然》杂志发表了这项成果。

许多手性敏感的光-物质相互作用是由手性电子动力学控制的。因此，利用手性现象的先进技术的发展将极大地受益于在自然阿秒时间尺度上测量和控制手性电子动力学。迄今为止，由于缺乏具有特征的圆偏振阿秒脉冲，这种努力受到了阻碍，这一障碍最近已被克服。 

研究组介绍了阿秒脉冲的手性光谱学，并演示了阿秒相干控制光电子圆二色性（PECD），以及测量手性分子的前向-后向和角度分辨光电离延迟中的手性不对称性。结果发现，与单光子电离相比，共旋转阿秒和近红外（IR）脉冲可以使PECD几乎翻一番，甚至改变其符号。

研究组证明，手性光电离延迟取决于光传播框架中光电发射的极角和方位角，需要3D动量分辨率。他们测量了高达60as的向前-向后手性敏感延迟和高达240as的极角分辨光电离延迟，其中包括源自连续体-连续体跃迁中手性的约60as的不对称性。阿秒手性光谱学为在电子时间尺度上定量理解和控制手性分子的动力学打开了大门。

附：英文原文

Title: Attosecond control and measurement of chiral photoionization dynamics

Author: Han, Meng, Ji, Jia-Bao, Blech, Alexander, Goetz, R. Esteban, Allison, Corbin, Greenman, Loren, Koch, Christiane P., Wrner, Hans Jakob

Issue&Volume: 2025-08-27

Abstract: Many chirality-sensitive light–matter interactions are governed by chiral electron dynamics. Therefore, the development of advanced technologies making use of chiral phenomena would critically benefit from measuring and controlling chiral electron dynamics on their natural attosecond timescales. Such endeavours have so far been hampered by the lack of characterized circularly polarized attosecond pulses, an obstacle that has recently been overcome1,2. Here we introduce chiroptical spectroscopy with attosecond pulses and demonstrate attosecond coherent control over photoelectron circular dichroism (PECD)3,4, as well as the measurement of chiral asymmetries in the forward–backward and angle-resolved photoionization delays of chiral molecules. We show that co-rotating attosecond and near-infrared (IR) pulses can nearly double the PECD and even change its sign compared with single-photon ionization. We demonstrate that chiral photoionization delays depend on both polar and azimuthal angles of photoemission in the light-propagation frame, requiring 3D momentum resolution. We measure forward–backward chiral-sensitive delays of up to 60as and polar-angle-resolved photoionization delays of up to 240as, which include an asymmetry of about 60as originating from chirality in the continuum–continuum transitions. Attosecond chiroptical spectroscopy opens the door to quantitatively understanding and controlling the dynamics of chiral molecules on the electronic timescale.

DOI: 10.1038/s41586-025-09455-4

Source: https://www.nature.com/articles/s41586-025-09455-4