Origin of the metamagnetic transitions in Y0.9Tb0.1Fe2D4.3

Deuterium insertion was used to tune the magnetic properties of Y0.9Tb0.1Fe2 Laves phase towards an itinerant electron metamagnetic (IEM) behavior. The latter is highly sensitive to chemical changes and external parameters. The structural and magnetic properties of Y0.9Tb0.1Fe2D4.3 were investigated using various neutron powder diffraction experiments in addition to magnetic measurements under steady and pulsed high magnetic fields up to 60 T. The deuteride crystallizes in a monoclinic structure (Pc space group) with 4.3 D atoms located in 18 tetrahedral interstitial sites. At zero field, it undergoes a ferrimagnetic-antiferromagnetic (FiM-AFM) transition at TM0 = 90 K, accompanied by an anisotropic magnetostriction and a negative cell volume expansion of 0.6 %. A second AFM-PM transition is observed at 146 K. Under pulsed magnetic field at 4.2 K, the deuteride displays a multistep magnetic behavior from ferrimagnetic to a ferromagnetic state, which can be attributed to a stepwise rotation of the Tb moments. The ZFC-FC magnetization curves at low fields exhibit an irreversibility below 90 K, followed by a sharp decrease in magnetization at the FM-AFM transition. Between 90 K and 130 K, the magnetization curves display an IEM behavior, with the transition field increasing linearly with temperature. Monoclinic Y0.9Tb0.1Fe2D4.3 undergoes different types of metamagnetic transitions: a forced ferri-ferromagnetic transition at 4.2 K and Itinerant electron metamagnetic transitions above 90 K. [Display omitted] •Y0.9Tb0.1Fe2D4.3 crystallizes in a monoclinic structure with Pc space group.•At 4.2 K it exhibits multistep changes from ferrimagnetic to ferromagnetic states.•A FM-AFM transition occurs at 91 K with an anisotropic cell volume contraction.•Above 91 K the M(B) curves show an IEM behavior with a linear increase of BTrans.•An AFM-PM transition is observed at 146 K.