TY - JOUR AB - Here we demonstrate a new monoclinic iron oxide phase (μ-Fe2O3), epitaxially stabilized by growth on (010) β-Ga2O3. Density functional theory (DFT) calculations find that the lattice parameters of freestanding μ-Fe2O3 are within ∼1% of those of β-Ga2O3, and that its energy of formation is comparable to that of naturally abundant Fe2O3 polytypes. A superlattice of μ-Fe2O3/β-Ga2O3 is grown by plasma assisted molecular beam epitaxy, with resulting high-resolution X-ray diffraction (XRD) measurements indicating that the μ-Fe2O3 layers are lattice-matched to the substrate. The measured out-of-plane (b) lattice parameter of 3.12 ± 0.4 Å is in agreement with the predicted lattice constants and atomic-resolution scanning transmission electron microscopy (STEM) images confirm complete registry of the μ-Fe2O3 layers with β-Ga2O3. Finally, DFT modeling predicts that bulk μ-Fe2O3 is antiferromagnetic, while the interface region between μ-Fe2O3 and β-Ga2O3 leads to ferromagnetic coupling between interface Fe3+ cations selectively occupying tetrahedral positions. Magnetic hysteresis persisting to room temperature is observed via SQUID measurements, consistent with the computationally predicted interface magnetism. © AU - Jamison,JS AU - May,BJ AU - Deitz,JI AU - Chien,SC AU - McComb,DW AU - Grassman,TJ AU - Windl,W AU - Myers,RC DO - 10.1021/acs.cgd.9b00029 EP - 4211 PY - 2019/// SN - 1528-7483 SP - 4205 TI - Ferromagnetic Epitaxial μ-Fe<inf>2</inf>O<inf>3</inf> on β-Ga<inf>2</inf>O<inf>3</inf>: A New Monoclinic Form of Fe<inf>2</inf>O<inf>3</inf> T2 - Crystal Growth and Design UR - http://dx.doi.org/10.1021/acs.cgd.9b00029 VL - 19 ER -