Room‐temperature multiferroic characteristics and unique vortex domain structures of h ‐Yb 1− x In x FeO 3 solid solutions

Abstract Hexagonal rare‐earth ferrites ( h ‐RFeO 3 ) have attracted much scientific attention due to their room‐temperature multiferroicity. However, it is still a hard job to obtain h ‐RFeO 3 bulk materials because of the meta‐stability of such hexagonal phase, and the evaluation of room‐temperature ferroelectric and magnetoelectric characteristics in such materials is also a challengeable issue. In the present work, Yb 1− x In x FeO 3 ceramics with the stable hexagonal structure were obtained by introducing chemical pressure, where the unique ferroelectric domain structures of sixfold vortex combined with tenfold vortex with a typical size of ~400 nm were determined. Symmetry of the present system evolved from centrosymmetric orthorhombic Pbnm ( x = 0–0.4) to non‐centrosymmetric hexagonal P6 3 cm ( x = 0.5 and 0.6) with a ferroelectric polarization up to 3.2 μC/cm 2 , and finally to centrosymmetric hexagonal P6 3 / mmc ( x = 0.7 and 0.8). The Curie point decreased monotonically from 723 K to a temperature below room temperature with increasing x, and the antiferromagnetic phase transition above room temperature was determined for all compositions. Meanwhile, a large linear magnetoelectric coefficient ( α ME ) up to 0.96 mV/cm Oe was obtained at room temperature, and this indicated the great application potential for magnetoelectric devices.