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arXiv · 2004.08215

Advanced data analysis procedure for hard x-ray resonant magnetic reflectivity discussed for Pt thin film samples of various complexity

Jan Krieft·Dominik Graulich·Anastasiia Moskaltsova·Laurence Bouchenoire·Sonia Francoual·Timo Kuschel
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Abstract

X-ray resonant magnetic reflectivity (XRMR) is a powerful method to determine the optical, structural and magnetic depth profiles of a variety of thin films. Here, we investigate samples of different complexity all measured at the Pt L$_3$ absorption edge to determine the optimal procedure for the analysis of the experimental XRMR curves, especially for nontrivial bi- and multilayer samples that include differently bonded Pt from layer to layer. The software tool ReMagX is used to fit these data and model the magnetooptic depth profiles based on a highly adaptable layer stack which is modified to be a more precise and physically consistent representation of the real multilayer system. Various fitting algorithms, iterative optimization approaches and a detailed analysis of the asymmetry ratio features as well as $\chi^2$ (goodness of fit) landscapes are utilized to improve the agreement between measurements and simulations. We present a step-by-step analysis procedure tailored to the Pt thin film systems to take advantage of the excellent magnetic sensitivity and depth resolution of XRMR.

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Jan Krieft, Dominik Graulich, Anastasiia Moskaltsova, Laurence Bouchenoire, Sonia Francoual, Timo Kuschel. 2020-04-17. Advanced data analysis procedure for hard x-ray resonant magnetic reflectivity discussed for Pt thin film samples of various complexity. https://doi.org/10.1088/1361-6463/ab8fdc

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