Charge order, enhanced orbital moment, and absence of magnetic frustration in layered multiferroic LuFe₂O₄

Electronic and magnetic properties of the charge ordered phase of LuFe₂O₄ are investigated by means of x-ray spectroscopic and theoretical electronic structure approaches. LuFe₂O₄ is a compound showing fascinating magnetoelectric coupling via charge ordering. Here, we identify the spin ground state of LuFe₂O₄ in the charge ordered phase to be a 2:1 ferrimagnetic configuration, ruling out a frustrated magnetic state. An enhanced orbital moment may enhance the magnetoelectric coupling. Furthermore, we determine the densities of states and the corresponding correlation potentials by means of x-ray photoelectron and emission spectroscopies, as well as electronic structure calculations.