Large Polarization Switching and High-Temperature Magnetoelectric Coupling in Multiferroic GaFeO3 Systems

GaFeO3-type iron oxides are promising multiferroics due to the coexistence of large spontaneous magnetization and polarization near room temperature. However, the high leakage current and difficulties associated with synthesizing single crystals E-induced make it difficult to achieve two important features in the system: a P switching large ferroelectric polarization switching and magnetoelectric coupling at a high-temperature region. Herein, we report successful achievement of these features by preparing high-quality Sc-doped GaFeO3 single crystals (ScxGa1-x/2Fe1-x/2O3 with x= 0-0.3) using the floating zone method. The x >= 0.05 crystals exhibit a leakage current 10(4) times lower than the x = 0 crystals, highlighting the importance of Sc doping. Because of the reduced leakage current, the Sc-doped crystals exhibit large ferroelectric polarization switching along the c-axis with a remanent polarization of 22-25 mu C/cm(2), which is close to the theoretically predicted polarization value of 25-28 mu C/cm(2). In addition, the Sc-doped crystals exhibit ferrimagnetism with magnetic anisotropy along the a-axis. Furthermore, a magnetic-field-induced modulation of polarization is observed in the x = 0.15 crystal even at a relatively high temperature, i.e., 100 K.

Automated summary

GaFeO3-type iron oxides are promising multiferroics with large spontaneous magnetization and polarization, but the difficulties in synthesizing single crystals and high leakage current have hindered achieving key features in the system. By doping Sc into GaFeO3 single crystals, features such as reduced leakage current, large ferroelectric polarization switching, and magnetoelectric coupling have been successfully achieved, demonstrating the potential of multiferroics.