Magnetism of mass-selected FeRh B2 nanocrystals in epitaxy on perovskite oxide

Near equiatomic composition, FeRh bulk alloys exhibit a CsCl-type (B2) chemically ordered phase related to a metamagnetic transition from an antiferromagnetic (AFM) to a ferromagnetic (FM) state close to ambient. Recently, we underlined the main role of Rh atoms on the metamagnetic transition for samples with high-density FeRh nanoparticles assemblies, where Rh kept a residual FM signature even at low temperature. The objective of this proposal is to study low-density samples, of mass-selected FeRh nanoparticles (NPs) grown on perovskite oxide, from X-ray absorption spectroscopy and magnetic circular dichroism (XAS/XMCD) experiments at Fe K and Rh L-edges at ID12 to explore interfacial strain effects on the magnetic order of epitaxial FeRh nanoparticles. Both use of quarter-wave plate to enhance the circular polarization rate and SDD with appropriate energy filter mounted in the 8T-cryomagnet would improve the signal to noise ratio in such diluted hybrid-nanostructures.