Achieving few-femtosecond time-sorting at hard X-ray free-electron lasers

作者：Harmand, M.^*; Coffee, R.; Bionta, M. R.; Chollet, M.; French, D.; Zhu, D.; Fritz, D. M.; Lemke, H. T.; Medvedev, N.; Ziaja, B.; Toleikis, S.; Cammarata, M.

来源：Nature Photonics, 2013, 7(3): 215-218.

DOI：10.1038/NPHOTON.2013.11

• SOLIDS

Recently, few-femtosecond pulses have become available at hard X-ray free-electron lasers. Coupled with the available sub-10 fs optical pulses, investigations into few-femtosecond dynamics are not far off. However, achieving sufficient synchronization between optical lasers and X-ray pulses continues to be challenging. We report a 'measure-and-sort' approach, which achieves sub-10 fs root-mean-squared (r.m.s.) error measurement at hard X-ray FELs, far beyond the 100-200 fs r.m.s. jitter limitations. This timing diagnostic, now routinely available at the Linac Coherent Light Source (LCLS), is based on ultrafast free-carrier generation in optically transparent materials. Correlation between two independent measurements enables unambiguous demonstration of fs r.m.s. error in reporting the optical/X-ray delay, with single shot error suggesting the possibility of reaching few-femtosecond resolution.

• 出版日期2013-3
• 单位中国地震局