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Updated: Jun 25, 2026

Hyperspectral Imaging as a Tool to Study Optical Anisotropy in Lanthanide-Based Molecular Single Crystals
Published on: April 14, 2020
Electronic structure and nesting-driven enhancement of the RKKY interaction at the magnetic ordering propagation
D S Inosov1, D V Evtushinsky, A Koitzsch
1Leibniz Institut für Festkörper- und Werkstoffforschung Dresden, D-01171 Dresden, Germany.
Abstract:
Measurements of the low-energy electronic structure in Gd2PdSi3 and Tb2PdSi3 by means of angle-resolved photoelectron spectroscopy reveal a Fermi surface consisting of an electron barrel at the Gamma point surrounded by spindle-shaped electron pockets originating from the same band. The calculated momentum-dependent RKKY coupling strength is peaked at the 1/2GammaK wave vector, which coincides with the propagation vector of the low-temperature in-plane magnetic order observed by neutron diffraction, thereby demonstrating the decisive role of the Fermi surface geometry in explaining the complex magnetic ground state of ternary rare earth silicides.
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