Bagschik Kai, Wagner Jochen, Buß Ralph, Riepp Matthias, Philippi-Kobs André, Müller Leonard, Buck Jens, Trinter Florian, Scholz Frank, Seltmann Jörn, Hoesch Moritz, Viefhaus Jens, Grübel Gerhard, Oepen Hans Peter, Frömter Robert
Opt Express. 2020 Mar 2;28(5):7282-7300. doi: 10.1364/OE.382608.
We present a systematic 2D spatial-coherence analysis of the soft-X-ray beamline P04 at PETRA III for various beamline configurations. The influence of two different beam-defining apertures on the spatial coherence properties of the beam is discussed and optimal conditions for coherence-based experiments are found. A significant degradation of the spatial coherence in the vertical direction has been measured and sources of this degradation are identified and discussed. The Fourier-analysis method, which gives fast and simple access to the 2D spatial coherence function of the X-ray beam, is used for the experiment. Here, we exploit the charge scattering of a disordered nanodot sample allowing the use of arbitrary X-ray photon energies with this method.
我们对PETRA III的软X射线光束线P04在各种光束线配置下进行了系统的二维空间相干性分析。讨论了两种不同的光束定义孔径对光束空间相干特性的影响，并找到了基于相干性实验的最佳条件。测量了垂直方向上空间相干性的显著退化，并确定和讨论了这种退化的来源。实验采用了傅里叶分析方法，该方法能够快速简便地获取X射线光束的二维空间相干函数。在这里，我们利用无序纳米点样品的电荷散射，使得该方法能够使用任意X射线光子能量。
