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arXiv · 2512.24191

Soft x-rays with Orbital Angular Momentum for resonant scattering experiments at the SOLEIL synchrotron

Pietro Carrara·Franck Fortuna·Renaud Delaunay·Joan Vila-Comamala·Benedikt Rösner·Christian David·Stefania Pizzini·Clément Fourniols·Laurent Vila·Matteo Pancaldi·Carlo Spezzani·Flavio Capotondi·Pierre Nonnon·Mauro Fanciulli·Thierry Ruchon·Nicolas Jaouen·Horia Popescu·Maurizio Sacchi
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Abstract

The paper presents a comprehensive description of a new setup implemented and commissioned at the SEXTANTS beamline of the SOLEIL synchrotron for absorption and scattering experiments with x-ray beams carrying an orbital angular momentum, also known as twisted x-ray beams. Two alternative methods have been implemented, based on the use of either spiral zone plates or fork gratings devices, and we show how they can be used for both defining and assessing the orbital angular momentum of an x-ray beam. We show also how multiple devices can be used in sequence to define an integer arithmetic of the orbital angular momentum of the final x-ray beam. Finally, we report the results of the first resonant scattering pilot experiments in transmission and reflection mode, intended to assess the feasibility of future users measurements. The availability of twisted soft x-rays complements the range of experimental techniques in elastic, resonant and coherent scattering available at the SEXTANTS beamline of the SOLEIL synchrotron.

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Pietro Carrara, Franck Fortuna, Renaud Delaunay, Joan Vila-Comamala, Benedikt Rösner, Christian David, Stefania Pizzini, Clément Fourniols, Laurent Vila, Matteo Pancaldi, Carlo Spezzani, Flavio Capotondi, Pierre Nonnon, Mauro Fanciulli, Thierry Ruchon, Nicolas Jaouen, Horia Popescu, Maurizio Sacchi. 2025-12-30. Soft x-rays with Orbital Angular Momentum for resonant scattering experiments at the SOLEIL synchrotron. https://arxiv.org/abs/2512.24191

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