Effect of surface magnetism on the x-ray spectra of hollow atoms

P. Dergham; C. Prigent; Ch. V. Ahmad A. Brassart; L. Duval; E. Lamour; S. Macé; S. Steydli; E. M. Tosi; D. Vernhet; M. Trassinelli

arXiv · 2506.15003

Effect of surface magnetism on the x-ray spectra of hollow atoms

P. Dergham·C. Prigent·Ch. V. Ahmad A. Brassart·L. Duval·E. Lamour·S. Macé·S. Steydli·E. M. Tosi·D. Vernhet·M. Trassinelli

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Abstract

We present evidence that the detection of surface magnetism without the application of an external magnetic field is possible by studying the x-ray emission of highly charged ions interacting at grazing incidence with the sample. Measuring the 3 keV $n=2 \to 1$ transition in the interaction of Ar\textsuperscript{17+} with a nickel sample at various temperatures gives access to the $n=2$ ion population. The latter evolves from a half-filled to a full shell during the ferro-paramagnetic phase transition of the sample, with the ferromagnetic phase reflecting the filling blocking due to Pauli principle. This finding puts an end to a longstanding controversy arising from contradictory studies of ion--surface interaction using Auger spectroscopy.

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P. Dergham, C. Prigent, Ch. V. Ahmad A. Brassart, L. Duval, E. Lamour, S. Macé, S. Steydli, E. M. Tosi, D. Vernhet, M. Trassinelli. 2025-06-17. Effect of surface magnetism on the x-ray spectra of hollow atoms. https://arxiv.org/abs/2506.15003

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