Prediction of huge X-ray Faraday rotation at the Gd N_4,5 threshold

X-ray absorption spectra in a wide energy range around the 4d-4f excitation threshold of Gd were recorded by total electron yield from in-plane magnetized Gd metal films. Matching the experimental spectra to tabulated absorption data reveals unprecedented short light absorption lengths down to 3 nm. The associated real parts of the refractive index for circularly polarized light propagating parallel or antiparallel to the Gd magnetization, determined through the Kramers-Kronig transformation, correspond to a magneto-optical Faraday rotation of 0.7 degrees per atomic layer. This finding shall allow the study of magnetic structure and magnetization dynamics of lanthanide elements in nanosize systems and dilute alloys.Comment: 4 pages, 2 figures, final version resubmitted to Phys. Rev. B, Brief Reports. Minor change

René d'Anjou (1409 - 1480): pouvoirs et gouvernement

Actes du colloque d\u27Angers (2009) consacré à la place de René d\u27Anjou comme gouvernant dans ses différents territoires (Anjou, Provence, Lorraine et Bar, royaume de Naples...). Quatre thèmes sont étudiés : prise et exercice du pouvoir ; lieux, institutions et personnel de l\u27État princier ; place de René dans l\u27histoire politique du XVe siècle en France et hors du royaume ; culture, pouvoir et gouvernement

Local order in disordered materials using X-ray anomalous scattering

Synchrotron radiation has made possible the development of X-rays anomalous scattering. First developped for the local order study in disordered materials, it can be applied to systems having a crystalline feature. We present the fundamentals of this technique, then we discuss its possibilities and its limitations through the determination of the atomic arrangement in amorphous NiZr alloy and in an unsupported Ni-Mo hydrodésulfurization catalyst

DIFFERENTIAL ANOMALOUS X-RAY SCATTERING STUDY OF AN UNSUPPORTED Ni-Mo SULFIDE CATALYST

L'utilisation de la diffusion anomale différentielle au seuil d'absorption K du Ni a permis de séparer, dans un catalyseur d'hydrodésulfuration massique, la contribution des atomes promoteurs Ni, du diagramme de diffraction global. Ainsi il a été possible d'extraire des informations concernant la situation du Ni dans le catalyseur qui confirment directement la localisation des ions promoteurs sur les bords du catalyseur.Using the differential anomalous scattering near the Ni K-edge, it has been to separate the contribution of the Ni-promotor atoms, from the total diffraction pattern of a hydrodesulfurization unsupported catalyst. Thus informations concerning the Ni situation in the catalyst have been obtained which directly show that the Ni promotors are located at the edges of catalyst

Element specific magnetization redistribution at YBa2Cu3O7 La2 3Ca1 3MnO3 interfaces

International audienc

XRMS Quantitative Study at the L2 and L3 Edges of Nd in Nd2Fe14B

Room-temperature measurements o f the asymmetry ratio of the XRMS signal on a Nd2Fe14B single crystal in the high temperature phase for several Bragg reflections at L2,3 edges of Nd are presented. The experimental results can be qualitatively described by taking into account only the dipolar electronic transitions but the quantitative disagreement suggests that a quadnipolar transition should be introduced into the calculation to achieve a more accurate description of the observed signals