Structure, Ferroelectricity, and Magnetism in Self‐Assembled BiFeO₃–CoFe₂O₄ Nanocomposites on (110)‐LaAlO₃ Substrates

Abstract

Abstract A strain‐driven BiFeO 3 (BFO) tetragonal to rhombohedral phase transition is demonstrated in self‐assembled BiFeO 3 ‐CoFe 2 O 4 (BFO‐CFO) nanocomposites on LaAlO 3 (110)‐oriented substrates with varying thickness. The CFO forms parallel nanoscale fin‐shaped structures within a BFO matrix. Out‐of‐plane lattice strain from the BFO/CFO interfaces stabilizes the BFO rhombohedral‐like phase. The BFO exhibits a range of ferroelectric textures including stripe domains and centered domain arrangements, and the magnetic anisotropy of CFO shows a thickness‐dependent reorientation.