Publications by authors named "A Stunault"

Polarized neutron diffraction is used to study in depth the magnetic properties of the heterometallic compound [NH(CH)][FeFe(HCOO)] and give insight into its magnetic behaviour, addressing open questions that will contribute to a better understanding of this attention-grabbing material and other related ones. Previous results revealed that upon cooling, the magnetic moments of the Fe and Fe sites do not order simultaneously: the magnetization of the Fe site increases faster than that of the Fe sites. Unpolarized neutron diffraction measurements at 2 K with no external field revealed some discrepancies in the saturation value of the magnetic signal on the Fe sites and in the ferromagnetic moment along the axis.

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Morphological and structural properties of amorphous disaccharide lactulose (CHO), obtained by four different amorphization methods (milling, quenching of the melt form, spray-drying, and freeze-drying), are investigated by scanning electron microscopy, polarized neutron scattering, and molecular dynamics simulations. While major differences on the morphology of the different amorphous samples are revealed by scanning electron microscopy images, only subtle structural differences have been found by polarized neutron scattering. Microstructure of the milled sample appears slightly different from the other amorphized materials with the presence of remaining crystalline germs which are not detected by X-ray diffraction.

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The scope of magnetic neutron scattering has been expanded by the observation of electronic Dirac dipoles (anapoles) that are polar (parity odd) and magnetic (time odd). A zero-magnetization ferromagnet Sm_{0.976}Gd_{0.

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Polarised neutron diffraction measurements have been made on HoFeO single crystals magnetised in both the [0 0 1] and [1 0 0] directions (Pbnm setting). The polarisation dependencies of Bragg reflection intensities were measured both with a high field of [Formula: see text] T parallel to [0 0 1] at [Formula: see text] K and with the lower field [Formula: see text] T parallel to [1 0 0] at [Formula: see text] K. A Fourier projection of magnetization induced parallel to [0 0 1], made using the hk0 reflections measured in 9 T, indicates that almost all of it is due to alignment of Ho moments.

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CeRhIn(5) is an itinerant magnet where the Ce(3+) spins order in a simple helical phase. We investigate the spin excitations and observe sharp spin waves parameterized by a nearest-neighbor exchange, J(RKKY)=0.88±0.

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