近日，瑞士苏黎世联邦理工学院Hans Jakob Wörner团队报道了自压缩波形稳定光瞬态实现水窗阿秒光谱学。这一研究成果发表在2025年11月13日出版的《自然—光子学》杂志上。

利用大芯径空心毛细光纤和长波长驱动脉冲在太瓦级别下实现孤子自压缩的演示，已为台式超快光谱实验开辟了新的可能性。

研究组报道了相位稳定的亚周期自压缩光瞬态的产生，以及对其光场的场分辨和相位分辨采样。他们展示了自压缩光瞬态的直接原位测量，其持续时间短至2.5 ± 0.2 fs，这在1,366纳米的中心波长下相当于半个光周期，并确定了其波形的相位偏移。研究组将这些瞬态应用于软X射线高次谐波产生和阿秒X射线吸收光谱。

在250电子伏特能量下的阿秒瞬态吸收光谱，证明了亚周期光瞬态在具有极限时间分辨率的实验中的实用性。该工作报道的进展，融合了自压缩且相位表征的光瞬态所提供的深度亚周期时间分辨率，并展示了其在水窗阿秒X射线吸收光谱中的应用，从而推动了可达到时间分辨率的边界。

附：英文原文

Title: Self-compressed waveform-stable light transients enabling water-window attosecond spectroscopy

Author: Utrio Lanfaloni, Valentina, Vismarra, Federico, Ardali, Emir, Monahan, Nicholas, Wiese, Joss, Kopp, Tristan, Ardana-Lamas, Fernando, Fazio, Giuseppe, Redaelli, Leonardo, Pertot, Yoann, Zinchenko, Kristina, Balinas, Tadas, Wrner, Hans Jakob

Issue&Volume: 2025-11-13

Abstract: The demonstration of soliton self-compression in the terawatt-level regime using large-core hollow capillary fibres and long-wavelength driving pulses has opened new possibilities for tabletop ultrafast spectroscopy experiments. Here we report the creation of phase-stable sub-cycle self-compressed light transients, as well as their field- and phase-resolved optical field sampling. We demonstrate the direct in situ measurement of self-compressed light transients, reaching durations down to 2.5±0.2fs, which is half of an optical cycle at a centroid wavelength of 1,366nm, and determine their waveform phase offset. We apply these transients to soft X-ray high-harmonic generation and attosecond X-ray absorption spectroscopy. Attosecond transient absorption spectroscopy at 250eV demonstrates the utility of the sub-cycle light transients for experiments with ultimate temporal resolution. The advances reported in this work merge the deep sub-cycle temporal resolution offered by self-compressed, phase-characterized light transients and showcase their application for water-window attosecond X-ray absorption spectroscopy, pushing the boundaries of achievable temporal resolution.

DOI: 10.1038/s41566-025-01802-1

Source: https://www.nature.com/articles/s41566-025-01802-1