Pulse Laser Deposited GaFeO3 Thin Film Grown on FTO: Correlated Ferroic Orders and Strong Magnetodielectric Coupling at Room Temperature
Room-temperature single-phase multiferroics exhibiting coupled ferroelectric and magnetic order are promising candidates for next-generation magnetoelectric memory and spintronic technologies. Here, we report the growth of approximately 100.6 nm thick polycrystalline orthorhombic GaFeO3 thin films on fluorine-doped tin oxide-coated glass (FTO) substrates by pulsed laser deposition. Core-level X-ray photoelectron spectroscopy reveals a reduced Fe2+ concentration and suppressed oxygen-vacancy formation, contributing to reduced leakage current and improved ferroelectric characteristics. The films exhibit robust ferrimagnetism and ferroelectricity at room temperature, confirming the coexistence of ferroic orders within a single phase. Piezoresponse Force Microscopy further demonstrates reversible local polarization switching, accompanied by an asymmetric butterfly loop with coercive voltages of -0.31 V and +1.07 V. The films also exhibit a high relative dielectric constant of approximately 1700 with a relatively low dielectric loss tangent of approximately 2.83 at 1 MHz. Moreover, a significant magnetodielectric coefficient of approximately 2.3% is observed under a relatively small magnetic field of only 0.1 kOe, highlighting strong magnetoelectric coupling. These results establish GaFeO3 thin films as a promising platform for room-temperature multifunctional devices, mainly low-field magnetoelectric memory and spintronic architectures.