Beyond well-documented confinement and surface effects arising from the large internal surface and severely confining porosity of nanoporous hosts, the transport of nanoconfined fluids remains puzzling by many aspects. With striking examples such as memory, i.e. non-viscous, effects, intermittent dynamics and surface barriers, the dynamics of fluids in nanoconfinement challenges classical...
Following the proposed materialization of Kitaev-bond-dependent spin liquid physics in honeycomb lattices of heavy transition metals with 4d or 5d electrons [1], it has been proposed that this can be extended to 3d transition metals, in particular Co2+ [2]. A first step in validating the prospect of finding a quantum spin liquid is to demonstrate the presence of these anisotropic...
We will show in this contribution how the combination of SANS and SAXS allows for a detailed monitoring of the respective evolutions of the structure of fillers by SAXS and conformation of polymeric chains by SANS under uniaxial stretching at various elongation ratios in a nanocomposite made of spherical magnetic nanoparticles of γFe2O3 dispersed in a matrix of polystyrene (PS) chains [1]. The...
Dy2Ti2O7 and Ho2Ti2O7 classical spin ice compounds have been extensively studied over the past 30 years. Their excitations, described as emergent magnetic monopoles, exhibit very slow dynamics at low temperature, which manifests by a freezing and a strong irreversibility in Zero Field Cooled - Field Cooled (ZFC-FC) magnetization measurements. It has been proposed that in spin ices made of...
The European Spallation Source (ESS) will operate a suite of diffractometers. One of the first operational instruments will be DREAM [1], a diffractometer developed and built for ESS by the consortium Forschungszentrum Jülich (Germany) and Laboratoire Léon Brillouin (France).
To ensure smooth operation even for the first-time users, the ESS Data Management and Software Centre is developing an...
Small-angle neutron scattering (SANS) is a ubiquitous technique for the study of static & dynamic properties of condensed matter at the mesoscale. The ever-increasing demand in SANS beamtime requires the development of new instruments with high scientific throughputs.
The SAM project was submitted in that spirit during the 'Endurance 2' call of the Institut Laue Langevin (ILL). The...
L’imagerie neutronique, sensible aux noyaux atomiques plutôt qu’à la densité électronique, constitue un outil puissant pour l’étude des batteries Li-ion, permettant notamment d’observer des éléments peu détectables par les rayons X, comme l’hydrogène et le lithium-6. Dans cette étude, nous exploitons cette technique pour analyser la distribution locale du lithium et identifier les...
Pyrochlore oxides with the formula R2M2O7 (R representing a rare-earth element and M a metal ele-ment) consist of two interpenetrating pyrochlore lattices, and are a rich playground to stabilize unconven-tional magnetic frustrated phases [1]. In this family, Nd-based compounds exhibit intriguing physics due to the dipolar-octupolar nature of the Nd3+ ground state doublet [2]. In particular, at...
The modelling of adsorption or confinement of organic molecules in zeolite crystals is a long story, not only because of the infinite possibilities offered by the intrinseque properties of the guest molecules and of the framework topologies.
The simplest family of such inclusion compounds is probably the (dye@zeolite) one. A priori the properties arising from the inclusion of simple dyes,...
Hydrogen is the carbon-free fuel par excellence because its combustion emits only water. Research has focused on H2 storage in lightweight materials for the needs of vehicles, excluding clays due to their weight. But large-scale terrestrial storage for industrial applications does not require the same specifications. In this context, clay minerals offer several interesting properties, such as...
KTb3F10 is a terbium-based compound with a cubic structure (Fm-3m space group), in which the magnetic Tb ions form an unusual network of corner sharing octahedra [1-4]. Tb ions sit on the 24e Wyckoff site (C4n point group) and are surrounded by 8 fluorine atoms, forming a slightly distorted dodecahedra cage. Interestingly, because of the cubic three-fold symmetry, there are three possible...
Controlling the structure of polymer solutions near a solid surface is crucial for many industrial processes as it significantly impacts solution flow and influences slip at the interface. To date, only a few techniques have been developed to experimentally investigate this type of interface at the nanometric scale of solid/liquid interactions. In this study, we probe the interface between a...
We report the emergence of a polar metal phase in layered van der Waals compound FePSe$_3$. This Mott insulator with antiferromagnetic order offers a unique opportunity to fully tune an insulator into a polar metal state with pressure, without doping-induced disorder or impurities. Our synchrotron and neutron diffraction data unambiguously show a structural transition and loss of the inversion...
Since the shutdown of the Orphée reactor, France is missing a national neutron facility to support its scientific community. Neutron sources worldwide are progressively transitioning from traditional reactor-based sources (such as ILL, Orphée, and FRM II) to pulsed sources (ESS, SNS, J-PARC). In parallel, the development of High Current Accelerator-driven Neutron Sources (HiCANS) offers a...
Fluids at solid interfaces are central to key technologies in energy conversion, electrochemistry, and catalysis, yet their nanoscale dynamics remain only partially understood. On metallic surfaces, recent studies have revealed unconventional interfacial phenomena—including complex electrostatic screening, anomalous wetting behavior, and quantum friction—that call for new modeling tools...
SAXS emerged in India in the group of Raman, then in the fifties of Kratky centered on the study of the empty cell by André Guinier in France and a dialogue of Kratky and Porod with Svedberg about proteins in solution. In the seventies and eighties absolute scaling at low-q and asymptotic laws at high-q started to be measured and were concomitant to the birth of science at nano-scale. ...
