Giant room-temperature magnetodielectric response in the electronic ferroelectric LuFe2O4

A very large drop in dielectric constant upon application of small magnetic fields is observed at room temperature for LuFe2O4 (see figure). Such behavior is unprecedented and indicates a strong coupling of spins and electric dipoles at room temperature. This behavior of LuFe2O4 is apparently related to its ferroelectricity, which occurs through the highly unusual mechanism of Fe2+ and Fe3+ ordering.