High-intensity extreme ultraviolet (XUV) pulses from a free-electron laser can be used to create a nanoplasma in clusters. In reference Michiels etal (2020 Phys. Chem. Chem. Phys. 22 7828–34) we investigated the formation of excited states in an XUV-induced nanoplasma in ammonia clusters. In the present article we expand our previous study with a detailed analysis of the nanoplasma evolution and ion kinetics. We use a time-delayed UV laser as probe to ionize excited states of H and in the XUV-induced plasma. Employing covariance mapping techniques, we show that the correlated emission of protons plays an important role in the plasma dynamics. The time-dependent kinetic energy of the ions created by the probe laser is measured, revealing the charge neutralization of the cluster happens on a sub-picosecond timescale. Furthermore, we observe ro-vibrationally excited molecular hydrogen ions being ejected from the clusters. We rationalize our data through a qualitative model of a finite-size non-thermal plasma.

来自自由电子激光器的高强度极紫外（XUV）脉冲可用于在簇中创建纳米等离子体。在参考Michiels的等人（2020的PHY。化学式化学物理。 22 7828-34），我们研究在氨簇的XUV诱导nanoplasma激发态的形成。在本文中，我们通过对纳米等离子体的演变和离子动力学的详细分析来扩展先前的研究。我们使用延时紫外激光作为探针来电离H和H的激发态在XUV诱导的血浆中。利用协方差映射技术，我们表明质子的相关发射在等离子体动力学中起重要作用。测量了由探测激光产生的离子的时间相关动能，揭示了簇的电荷中和发生在亚皮秒级的时间范围内。此外，我们观察到从团簇中喷出的由ro振动激发的分子氢离子。我们通过有限尺寸的非热等离子体的定性模型来合理化我们的数据。