Detrended fluctuation analysis in x-ray photon correlation spectroscopy for determining coarsening dynamics in alloys

Grazing-Incidence Small Angle X-ray Scattering (GISAXS) and X-Ray Photon Correlation Spectroscopy (XPCS) studies of island growth in two different systems are presented: 5 ML of iron on MgO(001) and 10 ML of iron on Au(001). Due to a missing conducting surface Fe/MgO thinner than approximately 20 ML could not be studied previously by common methods like STM. Fe/Au(001) is interesting as atoms of gold diffuse easily through iron layers and form precipitates. The coarsening dynamics of these precipitates is investigated by XPCS in GISAXS geometry. Their growth depends on the crystallographic directions of the substrate and correlates with the morphology measured by STM microscopy. Measurements were performed at the ESRF in Grenoble.

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From Femtoseconds to Hours–Measuring Dynamics over 18 Orders of Magnitude with Coherent X-rays

Applied Sciences ◽

10.3390/app11136179 ◽

2021 ◽

Vol 11 (13) ◽

pp. 6179

Author(s):

Felix Lehmkühler ◽

Wojciech Roseker ◽

Gerhard Grübel

Keyword(s):

Time Scales ◽

Free Electron Laser ◽

Photon Correlation Spectroscopy ◽

Signal To Noise Ratio ◽

Coherent Scattering ◽

Correlation Spectroscopy ◽

X Rays ◽

Photon Correlation ◽

X Ray ◽

Scattering Technique

X-ray photon correlation spectroscopy (XPCS) enables the study of sample dynamics between micrometer and atomic length scales. As a coherent scattering technique, it benefits from the increased brilliance of the next-generation synchrotron radiation and Free-Electron Laser (FEL) sources. In this article, we will introduce the XPCS concepts and review the latest developments of XPCS with special attention on the extension of accessible time scales to sub-μs and the application of XPCS at FELs. Furthermore, we will discuss future opportunities of XPCS and the related technique X-ray speckle visibility spectroscopy (XSVS) at new X-ray sources. Due to its particular signal-to-noise ratio, the time scales accessible by XPCS scale with the square of the coherent flux, allowing to dramatically extend its applications. This will soon enable studies over more than 18 orders of magnitude in time by XPCS and XSVS.

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Atomic Migration Studies with X-Ray Photon Correlation Spectroscopy

Diffusion Foundations ◽

10.4028/www.scientific.net/df.2.73 ◽

2014 ◽

Vol 2 ◽

pp. 73-94 ◽

Cited By ~ 2

Author(s):

Markus Stana ◽

Manuel Ross ◽

Bogdan Sepiol

Keyword(s):

Low Temperatures ◽

Short Range ◽

Short Range Order ◽

Photon Correlation Spectroscopy ◽

Condensed Matter ◽

Correlation Spectroscopy ◽

Atomic Scale ◽

Photon Correlation ◽

X Ray ◽

Amorphous Systems

The new technique of atomic-scale X-ray Photon Correlation Spectroscopy (aXPCS) makesuse of a coherent X-ray beam to study the dynamics of various processes in condensed matter systems.Particularly atomistic migration mechanisms are still far from being understood in most of intermetallicalloys and in amorphous systems. Special emphasis must be given to the opportunity to measureatomistic diffusion at relatively low temperatures where such measurements were far out of reach withpreviously established methods. The importance of short-range order is demonstrated on the basis ofMonte Carlo simulations.

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Microscopic Dynamics of Liquid-Liquid Phase Separation and Domain Coarsening in a Protein Solution Revealed by X-Ray Photon Correlation Spectroscopy

Physical Review Letters ◽

10.1103/physrevlett.126.138004 ◽

2021 ◽

Vol 126 (13) ◽

Author(s):

Anita Girelli ◽

Hendrik Rahmann ◽

Nafisa Begam ◽

Anastasia Ragulskaya ◽

Mario Reiser ◽

...

Keyword(s):

Phase Separation ◽

Liquid Phase ◽

Photon Correlation Spectroscopy ◽

Correlation Spectroscopy ◽

Liquid Phase Separation ◽

Protein Solution ◽

Photon Correlation ◽

X Ray ◽

Domain Coarsening ◽

Liquid Liquid Phase Separation

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Distributed X-ray photon correlation spectroscopy data reduction using Hadoop MapReduce

Journal of Synchrotron Radiation ◽

10.1107/s160057751800601x ◽

2018 ◽

Vol 25 (4) ◽

pp. 1135-1143 ◽

Cited By ~ 6

Author(s):

Faisal Khan ◽

Suresh Narayanan ◽

Roger Sersted ◽

Nicholas Schwarz ◽

Alec Sandy

Keyword(s):

Real Time ◽

Photon Correlation Spectroscopy ◽

Correlation Spectroscopy ◽

Frame Rate ◽

Computational Techniques ◽

Complex Materials ◽

Photon Correlation ◽

X Ray ◽

Wide Range ◽

Recent Developments

Multi-speckle X-ray photon correlation spectroscopy (XPCS) is a powerful technique for characterizing the dynamic nature of complex materials over a range of time scales. XPCS has been successfully applied to study a wide range of systems. Recent developments in higher-frame-rate detectors, while aiding in the study of faster dynamical processes, creates large amounts of data that require parallel computational techniques to process in near real-time. Here, an implementation of the multi-tau and two-time autocorrelation algorithms using the Hadoop MapReduce framework for distributed computing is presented. The system scales well with regard to the increase in the data size, and has been serving the users of beamline 8-ID-I at the Advanced Photon Source for near real-time autocorrelations for the past five years.

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Demonstration of 3D Photon Correlation Spectroscopy in the hard X-ray regime

Optics Letters ◽

10.1364/ol.444190 ◽

2021 ◽

Author(s):

Wonhyuk Jo ◽

Rustam Rysov ◽

FABIAN WESTERMEIER ◽

Michael Walther ◽

Leonard Mueller ◽

...

Keyword(s):

Photon Correlation Spectroscopy ◽

Correlation Spectroscopy ◽

Photon Correlation ◽

X Ray

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Concentration fluctuations in a binary glass former investigated by x-ray photon correlation spectroscopy

The Journal of Chemical Physics ◽

10.1063/1.3431537 ◽

2010 ◽

Vol 132 (22) ◽

pp. 224505 ◽

Cited By ~ 21

Author(s):

Sebastian Schramm ◽

Thomas Blochowicz ◽

Emmanuel Gouirand ◽

Robert Wipf ◽

Bernd Stühn ◽

...

Keyword(s):

Photon Correlation Spectroscopy ◽

Correlation Spectroscopy ◽

Concentration Fluctuations ◽

Photon Correlation ◽

X Ray ◽

Binary Glass

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On the use of two-time correlation functions for X-ray photon correlation spectroscopy data analysis

Journal of Applied Crystallography ◽

10.1107/s1600576717000577 ◽

2017 ◽

Vol 50 (2) ◽

pp. 357-368 ◽

Cited By ~ 9

Author(s):

Oier Bikondoa

Keyword(s):

Correlation Functions ◽

Photon Correlation Spectroscopy ◽

Time Correlation ◽

Correlation Spectroscopy ◽

Time Correlation Functions ◽

Spectroscopy Data ◽

Photon Correlation ◽

X Ray ◽

Equilibrium Processes ◽

Time Correlations

Multi-time correlation functions are especially well suited to study non-equilibrium processes. In particular, two-time correlation functions are widely used in X-ray photon correlation experiments on systems out of equilibrium. One-time correlations are often extracted from two-time correlation functions at different sample ages. However, this way of analysing two-time correlation functions is not unique. Here, two methods to analyse two-time correlation functions are scrutinized, and three illustrative examples are used to discuss the implications for the evaluation of the correlation times and functional shape of the correlations.

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