Ferromagnetism at Room Temperature Induced by Spin Structure Change in BiFe1-xCoxO3 Thin Films

The coexistence and coupling of ferromagnetic and ferroelectric orders in a single material is crucial for realizing next-generation multifunctional applications. The coexistence of such orders is confirmed at room temperature in epitaxial thin films of BiFe1-xCoxO3 (x <= 0.15), which manifests a spin structure change from a low-temperature cycloidal one to a high-temperature collinear one with canted ferromagnetism.