Sun Yanwen, Carini Gabriella, Chollet Matthieu, Decker Franz-Josef, Dunne Mike, Fuoss Paul, Hruszkewycz Stephan O, Lane Thomas J, Nakahara Kazutaka, Nelson Silke, Robert Aymeric, Sato Takahiro, Song Sanghoon, Stephenson G Brian, Sutton Mark, Van Driel Tim B, Weninger Clemens, Zhu Diling
Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA.
Materials Science Division, Argonne National Laboratory, Lemont, Illinois 60439, USA.
Phys Rev Lett. 2021 Jul 30;127(5):058001. doi: 10.1103/PhysRevLett.127.058001.
We report observations of nanosecond nonuniform colloidal dynamics in a free flowing liquid jet using ultrafast x-ray speckle visibility spectroscopy. Utilizing a nanosecond double-bunch mode, the Linac Coherent Light Source free electron laser produced pairs of femtosecond coherent hard x-ray pulses. By exploring anisotropy in the visibility of summed speckle patterns which relates to the correlation functions, we evaluate not only the average particle flow rate in a colloidal nanoparticle jet, but also the nonuniform flow field within. The methodology presented here establishes the foundation for the study of nano- and atomic-scale inhomogeneous fluctuations in complex matter using x-ray free electron laser sources.
我们报告了使用超快X射线散斑可见度光谱法对自由流动液体射流中纳秒级非均匀胶体动力学的观测结果。利用纳秒双束模式，直线加速器相干光源自由电子激光产生了飞秒相干硬X射线脉冲对。通过探索与相关函数有关的总和散斑图案可见度中的各向异性，我们不仅评估了胶体纳米颗粒射流中的平均粒子流速，还评估了其中的非均匀流场。本文介绍的方法为使用X射线自由电子激光源研究复杂物质中的纳米和原子尺度非均匀涨落奠定了基础。
