Time-resolved x-ray imaging of a laser-induced nanoplasma and its neutral residuals
Time-resolved x-ray imaging of a laser-induced nanoplasma and its neutral residuals
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DOI：
10.1088/1367-2630/18/4/043017
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发表时间：
2016-04-13
影响因子：
3.3
通讯作者：
Moeller, T.
中科院分区：
文献类型：
--
作者：
Flueckiger, L.;Rupp, D.;Moeller, T.
个别的，大的气相氙团簇的演变，变成纳米等离子体的高功率红外激光脉冲，跟踪从飞秒到纳秒激光激发后，通过相干衍射成像，使用超短软X射线自由电子激光脉冲。随着时间延迟的增加，在高检测角下的散射信号的下降表明簇表面的软化。在这里，我们证明，第一次有代表性的散斑图案的一个新阶段的集群扩展氙集群纳秒照射后。分析所测得的平均散斑大小和强度分布的包络，揭示了内部密度波动的平均簇大小和长度尺度。测量的衍射图案再现散射模拟，假设该集群扩展与显着的内部密度波动激发后数百皮秒。
The evolution of individual, large gas-phase xenon clusters, turned into a nanoplasma by a high power infrared laser pulse, is tracked from femtoseconds up to nanoseconds after laser excitation via coherent diffractive imaging, using ultra-short soft x-ray free electron laser pulses. A decline of scattering signal at high detection angles with increasing time delay indicates a softening of the cluster surface. Here we demonstrate, for the first time a representative speckle pattern of a new stage of cluster expansion for xenon clusters after a nanosecond irradiation. The analysis of the measured average speckle size and the envelope of the intensity distribution reveals a mean cluster size and length scale of internal density fluctuations. The measured diffraction patterns were reproduced by scattering simulations which assumed that the cluster expands with pronounced internal density fluctuations hundreds of picoseconds after excitation.