| 1. |
- Jo, W., et al.
(author)
-
Nanosecond X-ray photon correlation spectroscopy using pulse time structure of a storage-ring source
- 2021
-
In: IUCrJ. - : International Union of Crystallography. - 2052-2525. ; 8, s. 124-130
-
Journal article (peer-reviewed)abstract
- X-ray photon correlation spectroscopy (XPCS) is a routine technique to study slow dynamics in complex systems at storage-ring sources. Achieving nanosecond time resolution with the conventional XPCS technique is, however, still an experimentally challenging task requiring fast detectors and sufficient photon flux. Here, the result of a nanosecond XPCS study of fast colloidal dynamics is shown by employing an adaptive gain integrating pixel detector (AGIPD) operated at frame rates of the intrinsic pulse structure of the storage ring. Correlation functions from single-pulse speckle patterns with the shortest correlation time of 192 ns have been calculated. These studies provide an important step towards routine fast XPCS studies at storage rings. © 2021.
|
|
| 2. |
- Bagschik, K., et al.
(author)
-
Spatial coherence determination from the Fourier analysis of a resonant soft X-ray magnetic speckle pattern
- 2016
-
In: Optics Express. - : Optical Society of America. - 1094-4087. ; 24:20, s. 23162-23176
-
Journal article (peer-reviewed)abstract
- We present a method to determine the two-dimensional spatial coherence of synchrotron radiation in the soft X-ray regime by analyzing the Fourier transform of the magnetic speckle pattern from a ferromagnetic film in a multidomain state. To corroborate the results, a Young's double-pinhole experiment has been performed. The transverse coherence lengths in vertical and horizontal direction of both approaches are in a good agreement. The method presented here is simple and gives a direct access to the coherence properties of synchrotron radiation without nanostructured test objects.
|
|
| 3. |
- Müller, L., et al.
(author)
-
Note : Soft X-ray transmission polarizer based on ferromagnetic thin films
- 2018
-
In: Review of Scientific Instruments. - : American Institute of Physics Inc.. - 0034-6748 .- 1089-7623. ; 89:3
-
Journal article (peer-reviewed)abstract
- A transmission polarizer for producing elliptically polarized soft X-ray radiation from linearly polarized light is presented. The setup is intended for use at synchrotron and free-electron laser beamlines that do not directly offer circularly polarized light for, e.g., X-ray magnetic circular dichroism (XMCD) measurements or holographic imaging. Here, we investigate the degree of ellipticity upon transmission of linearly polarized radiation through a cobalt thin film. The experiment was performed at a photon energy resonant to the Co L3-edge, i.e., 778 eV, and the polarization of the transmitted radiation was determined using a polarization analyzer that measures the directional dependence of photo electrons emitted from a gas target. Elliptically polarized radiation can be created at any absorption edge showing the XMCD effect by using the respective magnetic element.
|
|
| 4. |
- Zhou Hagström, Nanna, 1993-, et al.
(author)
-
Megahertz-rate Ultrafast X-ray Scattering and Holographic Imaging at the European XFEL
-
Other publication (other academic/artistic)abstract
- The advent of X-ray free-electron lasers (XFELs) has revolutionized fundamental science, from atomic to condensed matter physics, from chemistry to biology, giving researchers access to X-rays with unprecedented brightness, coherence, and pulse duration. All XFEL facilities built until recently provided X-ray pulses at a relatively low repetition rate, with limited data statistics. Here, we present the results from the first megahertz repetition rate X-ray scattering experiments at the Spectroscopy and Coherent Scattering (SCS) instrument of the European XFEL. We illustrate the experimental capabilities that the SCS instrument offers, resulting from the operation at MHz repetition rates and the availability of the novel DSSC 2D imaging detector. Time-resolved magnetic X-ray scattering and holographic imaging experiments in solid state samples were chosen as representative examples, providing an ideal test-bed for operation at megahertz rates. Nevertheless, our results are relevant and applicable to any other non-destructive XFEL experiments in the soft X-ray range.
|
|
| 5. |
- Zhou Hagström, Nanna, 1993-, et al.
(author)
-
Megahertz-rate ultrafast X-ray scattering and holographic imaging at the European XFEL
- 2022
-
In: Journal of Synchrotron Radiation. - : International Union of Crystallography (IUCr). - 0909-0495 .- 1600-5775. ; 29, s. 1454-1464
-
Journal article (peer-reviewed)abstract
- The advent of X-ray free-electron lasers (XFELs) has revolutionized fundamental science, from atomic to condensed matter physics, from chemistry to biology, giving researchers access to X-rays with unprecedented brightness, coherence and pulse duration. All XFEL facilities built until recently provided X-ray pulses at a relatively low repetition rate, with limited data statistics. Here, results from the first megahertz-repetition-rate X-ray scattering experiments at the Spectroscopy and Coherent Scattering (SCS) instrument of the European XFEL are presented. The experimental capabilities that the SCS instrument offers, resulting from the operation at megahertz repetition rates and the availability of the novel DSSC 2D imaging detector, are illustrated. Time-resolved magnetic X-ray scattering and holographic imaging experiments in solid state samples were chosen as representative, providing an ideal test-bed for operation at megahertz rates. Our results are relevant and applicable to any other non-destructive XFEL experiments in the soft X-ray range.
|
|
