近日，美国SLAC国家加速器实验室的Agostino Marinelli及其研究团队取得一项新进展。经过不懈努力，他们利用射线自由电子激光器实现阿秒泵浦探测光谱的实验论证。相关研究成果已于2024年4月11日在国际知名学术期刊《自然—光子学》上发表。

本文成功展示了双色X射线自由电子激光器生成和控制亚飞秒脉冲对的过程。通过角条纹诊断技术，研究人员测量了两个脉冲间的延迟，精准表征了X射线自由电子激光的群速度，并成功将脉冲延迟控制到低至270as的水平。

此外，研究人员还验证了这一技术在泵浦探测测量核电离对氨基酚中的应用。这些成果充分展现了进行亚飞秒分辨率和原子位点特异性泵浦探测实验的能力。

据悉，亚飞秒分辨率的泵浦探测实验是理解量子系统中电子动力学的关键。

附：英文原文

Title: Experimental demonstration of attosecond pump–probe spectroscopy with an X-ray free-electron laser

Author: Guo, Zhaoheng, Driver, Taran, Beauvarlet, Sandra, Cesar, David, Duris, Joseph, Franz, Paris L., Alexander, Oliver, Bohler, Dorian, Bostedt, Christoph, Averbukh, Vitali, Cheng, Xinxin, DiMauro, Louis F., Doumy, Gilles, Forbes, Ruaridh, Gessner, Oliver, Glownia, James M., Isele, Erik, Kamalov, Andrei, Larsen, Kirk A., Li, Siqi, Li, Xiang, Lin, Ming-Fu, McCracken, Gregory A., Obaid, Razib, ONeal, Jordan T., Robles, River R., Rolles, Daniel, Ruberti, Marco, Rudenko, Artem, Slaughter, Daniel S., Sudar, Nicholas S., Thierstein, Emily, Tuthill, Daniel, Ueda, Kiyoshi, Wang, Enliang, Wang, Anna L., Wang, Jun, Weber, Thorsten, Wolf, Thomas J. A., Young, Linda, Zhang, Zhen, Bucksbaum, Philip H., Marangos, Jon P., Kling, Matthias F., Huang, Zhirong, Walter, Peter, Inhester, Ludger, Berrah, Nora, Cryan, James P., Marinelli, Agostino

Issue&Volume: 2024-04-11

Abstract: Pump–probe experiments with subfemtosecond resolution are the key to understanding electronic dynamics in quantum systems. Here we demonstrate the generation and control of subfemtosecond pulse pairs from a two-colour X-ray free-electron laser. By measuring the delay between the two pulses with an angular streaking diagnostic, we characterize the group velocity of the X-ray free-electron laser and show control of the pulse delay down to 270as. We confirm the application of this technique to a pump–probe measurement in core-ionized para-aminophenol. These results reveal the ability to perform pump–probe experiments with subfemtosecond resolution and atomic site specificity.

DOI: 10.1038/s41566-024-01419-w

Source: https://www.nature.com/articles/s41566-024-01419-w