Valence-specific magnetization of the charge-ordered multiferroelectricLuFe2O4using soft x-ray magnetic circular dichroism under 30 T pulsed high magnetic fields

Abstract

LuFe${}_{2}$O${}_{4}$ is being actively studied in the context of an unconventional electronic ferroelectricity that appears due to charge ordering of $F\phantom{\rule{0}{0ex}}{e}^{2+}$ and $F\phantom{\rule{0}{0ex}}{e}^{3+}$ oxidation states. LuFe${}_{2}$O${}_{4}$ displays a high magneto-electric coupling, giant magnetic coercivity, and other unusual features, some of them highly controversial. In this study a group of researchers from Japan present their XMCD results in pulsed magnetic fields reaching 30 Tesla. Their technique allows them to measure valence-specific magnetization of $F\phantom{\rule{0}{0ex}}{e}^{2+}$ and $F\phantom{\rule{0}{0ex}}{e}^{3+}$ ions above and below the charge-ordering temperature and provides a unique view on the coupling between the charge and spin degrees of freedom in LuFe${}_{2}$O${}_{4}$.