Determination of the intersublattice exchange interactions in GdCo 12-x Fe x B 6 (x = 0-3) intermetallic compounds by high field magnetization measurements

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R2Co3-xSix (R = Pr, Nd, Sm, Gd) and R2Ni3-xSix (R = Gd-Er), new series of La2Ni3-type phases

International audienceIn this study, we have expanded our previous work on the Gd2(Co3-xSix) solid solution to form the family of R2(T3-xSix) compounds with a wide range of the rare earth metals (Pr, Nd, Sm, Gd, Tb, Dy, Ho and Er) by variation of the composition and, where necessary, the transition element (Co and Ni). We report the crystallographic and the magnetic properties of this La2Ni3-type series. The R2Co3-xSix compounds with R = Pr, Nd, Sm and Gd, undergo ferro- or ferrimagnetic transitions at TC ranging from 64 K (Nd) to 338 K (Gd) and the R2Ni3-xSix phases with R = Gd-Er display ferromagnetic order below TC from 96 K (Gd) to 7 K (Er)

Step-scan time-domain terahertz magnetospectroscopy

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Interplay of magnetism,Fermi surface reconstructions, and hidden order in the heavy-fermion material URu2Si2,

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High- field moment polarization in the ferromagnetic superconductor ucoge

International audienceWe report magnetization and magnetoresistivity measurements on the isostructural ferromagnetic superconductors UCoGe and URhGe in magnetic fields up to 60 T and temperatures from 1.5 to 80 K. At low temperature, a moment polarization in UCoGe in a field mu H-0 parallel to b of around 50 T leads to well-defined anomalies in both magnetization and magnetoresistivity. These anomalies vanish in temperatures higher than 30-40 K, where maxima in the magnetic susceptibility and the field-induced variation of the magnetoresistivity are found. A comparison is made between UCoGe and URhGe, where a moment reorientation in a magnetic field mu H-0 parallel to b of 12 T leads to field-induced reentrant superconductivity