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GdRu2Si2 is a centrosymmetric magnet in which a skyrmion lattice has recently been discovered. Here, we investigate the magnetic structure of the zero-field ground state using neutron diffraction on single crystal and polycrystalline 160GdRu2Si2. In addition to observing the principal propagation vectors q1 and q2, we discover higher-order magnetic satellites, notably q1+2q2. The appearance of these satellites is explained within the framework of a double-Q constant-moment solution. Using powder diffraction, we implement a quantitative refinement of this model. This structure, which contains vortexlike motifs, is shown to have a one-dimensional topological charge density.

Nd 2 Fe 14 B 's unsurpassed, hard magnetic properties for a wide range of temperatures result from a combination of a large volume magnetization from Fe and a strong single-ion anisotropy from Nd. Here, using finite temperature first-principles calculations, we focus on the other crucial roles played by the Fe atoms in maintaining the magnetic order on the Nd sublattices, and hence the large magnetic anisotropy, and directly generating significant uniaxial anisotropy at high temperatures. We identify effective spins for atomistic modeling from the material's interacting electrons and quantify pairwise and higher order, nonpairwise magnetic interactions among them. We find the Nd spins couple most strongly to spins on sites belonging to two specific Fe sublattices: 8 j 1 and 8 j 2 . Moreover, the Fe 8 j 1 sublattice also provides the electronic origin of the unusual, nonmonotonic temperature dependence of the anisotropy of Y 2 Fe 14 B . Our work provides atomic-level resolution of the properties of this fascinating magnetic material.

International audience; Dupilumab is a recombinant monoclonal IgG4 type antibody which inhibits IL4 and IL13 signaling. It is indicated in moderate to severe atopic dermatitis (AD) in adults and adolescents over 12 years of age. Its side effects include conjunctivitis and blepharoconjunctivitis, affecting between 4.7% and 28% of patients depending on the study. The incidence of conjunctivitis in patients treated with dupilumab for AD appears to be higher than placebo in clinical studies. This increase was not observed in patients treated with dupilumab for asthma or sinonasal polyposis. The risk factors for conjunctivitis in patients with AD are disease severity, pre-existence of conjunctivitis and low concentrations of dupilumab, but the pathophysiology of this disease is poorly understood. A literature search carried out in April and May 2020 showed an increase in the number of publications on the subject, but there are currently no official joint dermatologist-ophthalmologist recommendations for prevention and management. The objective of this article is to provide an overview of the status of this subject, to address the main questions raised by this type of conjunctivitis and to suggest a course of action for starting and continuing treatment with dupilumab in patients with AD, according to the recommendations of the French Ophthalmologist/Dermatologist group CEDRE.

Cr1/3NbS2 is a transition metal dichalcogenide that has been of significant interest due to its ability to host a magnetic chiral soliton lattice. Conventional and planar Hall measurements provide valuable insight into the detection of exotic spin structures in chiral magnets. We show that the presence of a giant planar Hall effect (PHE) can be attributed to a tilted soliton lattice in Cr1/3NbS2. Our detailed angular-dependent study shows the PHE and anisotropic magnetoresistance are intrinsically linked in complex noncoplanar magnets. From the conventional Hall signal we show the presence of a giant unconventional, likely topological Hall component that is the fingerprint of noncoplanar spin textures.

International audience; Wake-up effect is a major issue for ferroelectric HfO2-based memory devices. Here, two TiN/Hf0.5Zr0.5O2/TiN structures deposited by magnetron sputtering on silicon are compared. The maximum remanant polarization is higher than 21µC/cm² for both samples, a strong difference is observed in the electrical behavior. For the mesa sample, the difference between maximal and initial Pr is only 3µC/cm² whereas it is around 14µC/cm² in the non-mesa case. We discuss the root causes of these behaviors in light of structural results. Various applications have been suggested for fluorite-structure ferroelectrics due to their advantages over the conventional perovskite-structure ferroelectrics. In this presentation we will focus on (Hf,Zr)O2 (HZO) thin films deposition for the capacitor of Ferroelectric Random Access Memories (FRAM) in the 1Transitor-1Capacitor (1T-1C) model. (Hf,Zr)O2 thin films are studied to either fully understand the stabilization of the ferroelectric phase (f-phase) or to fit with industrial requirements. Samples are stacks of Si/TiN/Hf0.5Zr0.5O/TiN/Pt. All materials are grown by sputtering at room temperature following by a rapid thermal annealing at 450°C during 30 seconds under N2 atmosphere. The samples are called NM, and M. NM and M refers to two different architectures, respectively non-mesa and mesa structures. We report the fabrication of two samples deposited by magnetron sputtering with excellent performances, quite similar to samples deposited by Atomic Layer Deposition. Pr values are among the highest for samples deposited by sputtering. Although the N-sample and NM-samples show very close Pr values, the two samples show completely different electrical behaviors. During cycling, the increase of Pr value for the NM-sample is more than an order of magnitude higher than the M-sample. It is accompanied by a decrease of the endurance which is two order of magnitude higher for the NM-sample than for the M-sample. As electrical behaviors are not the same, for low stress conditions M-sample has a higher Pr value during cycling whereas for high stress conditions NM-sample has a higher Pr value during cycling. As a matter of fact, it has been proven that maximum Pr values are more sensitive to stress conditions than the structures themselves. The origins of the different electrical behaviors come from the micro-crystalline structures of the two samples, according to GIXRD results. The crystallization takes place during the annealing step. During annealing, M-sample is built with a TiN TE fully covering the HZO layer whereas the TiN covers only partially the HZO layer in case of the NM-sample. It induces different stress states which lead to two different micro-crystalline patterning. The M-sample shows no monoclinic peak, whereas the NM-sample shows many monoclinic orientations. It can explain the huge reduction of the wake-up effect.