Abstract:
Many current forthcoming applications of magnetic materials involve heterostructures or alloys containing magnetic and non-magnetic elements. X-ray Resonant (Coherent) Scattering is the technique of choice to probe such phenomena thanks to its element-selectivity and spatial sensitivity.

In this presentation I will introduce the experimental set-up that we developed at SOLEIL and illustrate their capabilities. SEXTANTS [1] is a beamline of the SOLEIL synchrotron, covering the 50-1700eV energy range dedicated to soft x-ray scattering. The resolving power exceeds 10000 and maximum flux on the sample ranges from 1×1014 (100 eV) to 2×1013 (1000 eV) ph./s/0.1% bw. The beamline main objective is the investigation of the electronic and magnetic properties of solids using three scattering techniques: resonant inelastic x-ray scattering (RIXS), x-ray resonant magnetic scattering (XRMS) and coherent x-ray scattering (CXS), the last one including also imaging via Fourier transform holography (FTH) [2, 3].

In the second part, several recent results obtained at SEXTANTS beamline will be presented, and in particular I will show that XRMS is the tool to study magnetic chirality in prototype Pt/Co multilayers in which Dzyaloshinskii-Morya interaction (DMI) is induced by the inversion symmetry breaking at the interfaces [3] and how it was possible to reveal the hybrid character of the magnetic structure in thick multilayer [4]. I will also present how one can manipulate this magnetic chirality either statically using magnetic field or at the femtosecond timescale using optical light [5].

In the last part I will present the latest development of resonant scattering and in particular how the use of the x-ray coherence already available at modern light source, and expected to increase by few order of magnitude in the planned upgrade sources, allow nowadays to image the sample with a spatial resolution of few tens of nanometers and a time resolution ranging from ns down to few ps timescale.

[1] M. Sacchi et al., Journal of Physics: Conference Series 425 (2013) 072018
[2] S. Eisebitt et al., Nature, 432, 885 (2004).
[3] H. Popescu et al., J. Synchr. Rad 26(1), 280-290 (2019)
[3] J.Y. Chauleau et al., Phys. Rev. Lett. 120, 037202 (2018).
[4] W. Legrand et al, Sci. Adv. 2018; 4:eaat0415 (2018).
[5] C. Léveillé et al., Nat. Communication 13, 1412 (2022).

*Corresponding author: nicolas.jaouen@synchrotron-soleil.fr

Bio:
Nicolas Jaouen graduated from the Institute National Polytechnique de Grenoble. He did his PhD at CNRS / Grenoble University Néel Institute under the supervision of J.M. Tonnerre and D. Raoux.

After that he worked as a Post Doc and Scientist on ID12 beamline at the ESRF under the supervision of A. Rogalev. After his Grenoble time, he moved to SOLEIL in order to build the SEXTANTS beamline at SOLEIL dedicated to soft x-ray elastic/inelastic scattering.

His research focus is on magnetic material, with an emphasis, these last years, on how to probe magnetic chirality using soft x-ray (coherent) resonant scattering

The CoWork webinar series is dedicated to the exploitation of the coherence properties of X-rays for advanced materials characterization, with a special focus on inverse microscopy techniques, such as Coherent Diffraction Imaging (CDI), Ptychography and Holography. It is an introduction to Coherent X-ray imaging methods to facilitate the access to advanced microscopy techniques to new users and it welcomes all researchers intrigued by the spectacular coherence properties of X-rays produced at modern synchrotron sources – of which MAX IV is a first example.