Room-temperature polarization switching and antiferromagnetic coupling in epitaxial (Ga,Fe)₂O₃/SrRuO₃ heterostructures

Room-temperature reversible remnant polarization of gallium ferrite thin-films is reported as a multiferroic material with non-zero order parameters of polarization and magnetization. With the addition of Fe ions in Ga sites, Ga_0.6Fe_1.4O₃ (GFO) thin films have been considered as potentially promising of multiferroicity. The b-axis oriented epitaxial GFO films were grown on SrRuO₃(111)/SrTiO₃(111). The six-fold symmetric in-plane epitaxy of the GFO films was confirmed using X-ray diffraction. The magnetic moment of the films was measured as a function of temperature and external magnetic field, which shows a room-temperature non-zero magnetization. Macroscopic and microscopic methods have been applied to demonstrate the polarization switching of the films. The remnant polarization is measured as 0.05 μC/cm². Reduction of leaky behaviors of the GFO films owing to the conducting oxide of SrRuO₃ will pave a way to take advantage of the room-temperature non-zero multi-orders for future non-volatile memory device applications.