Multiferroic-field coupling in ultrathin nanofilm halide perovskite at room temperature

New materials with unique properties and nanostructures are essential for high-efficiency multibit devices to implement next-generation core logic and memory functions. Herein, a high-quality single-phase ultrathin nanofilm organic–inorganic hybrid perovskite nanostructure without transition metals is proposed. (C₄H₉NH₃)₂PbI₂Br₂ is a multifield coupling material with ferroic orders coexisting at room temperature (300 K). The domain rotation is controlled by adjusting the electric field strength using magnetoelectricity and ferroelectricity. The responsiveness and phase controllability of ferromagnetism, ferroelectricity, and piezoelectricity in ultra-thin nanofilm hybrid perovskites are successfully controlled through the external electric field induced by the coupling between the ferroic orders at room temperature. This study shows that high-quality nanostructured perovskites are suitable materials for high-efficiency multibit devices.