近日，德国埃尔朗根-纽伦堡弗里德里希-亚历山大大学Jonas Heimerl团队研究了光学近场中的阿秒物理。相关论文于2025年11月12日发表在《自然—物理学》杂志上。

阿秒科学（用超短激光脉冲控制电子）正在发展成为光场驱动的电子技术。光场驱动的纳米结构为这种电子学提供了元素，这依赖于对光学近场电子动力学的理解。

研究组报告了载流子包络相相关电子能谱中的近场诱导低能条纹，即一种出现在强驱动纳米结构发射的直接电子中的光谱特征。这些条纹的产生是由于电子的质心加速度的亚周期灵敏度，这些电子被注入到强近场梯度中，这是由几个周期的光学波形引起的。它们实现了在亚周期时间尺度上跟踪直接和重新散射的电子发射，并提供对发射时电子动量宽度的访问。由于这种效应发生在直接电子信号中，因此可以控制发射电子的很大一部分，从而能够隔离具有高电荷密度的单个阿秒电子爆发。

附：英文原文

Title: Attosecond physics in optical near fields

Author: Heimerl, Jonas, Meier, Stefan, Herzig, Anne, Lpez Hoffmann, Felix, Seiffert, Lennart, Lesko, Daniel M. B., Hillmann, Simon, Wittigschlager, Simon, Weitz, Tobias, Fennel, Thomas, Hommelhoff, Peter

Issue&Volume: 2025-11-12

Abstract: Attosecond science—the control of electrons by ultrashort laser pulses—is developing into lightfield-driven, or petahertz, electronics. Optical-field-driven nanostructures provide elements for such electronics, which rely on understanding electron dynamics in the optical near field. Here we report near-field-induced low-energy stripes in carrier-envelope-phase-dependent electron spectra—a spectral feature that appears in the direct electrons emitted from a strongly driven nanostructure. These stripes arise from the subcycle sensitivity of the ponderomotive acceleration of electrons injected into a strong near-field gradient by a few-cycle optical waveform. They allow the tracking of direct and rescattered electron emissions on subcycle timescales and provide access to the electron momentum width at emission. Because this effect occurs in the direct electron signal, a large fraction of the emitted electrons can be steered, enabling the isolation of individual attosecond electron bursts with high charge density.

DOI: 10.1038/s41567-025-03093-3

Source: https://www.nature.com/articles/s41567-025-03093-3