Atomical‐Rippled‐Nanodomains Stabilized Large Polarization in BiSmCo ₂ O ₆ Double‐Perovskite Films

Abstract

Abstract Double‐perovskite ferroelectrics have attracted increasing attention due to their highly tunable structures, multifunctional coupling effects, and potential applications in next‐generation nonvolatile ferroelectric semiconductor devices. Here, an atomical‐rippled‐nanodomains (ARNs) are introduced to BiCoO 3 and SmCoO 3 solid solution double‐perovskite film due to its ferroelectric single‐domain coupling. By engineering triaxial tensile strain, the ferroelectric ARNs are robustly formed in BiSmCo 2 O 6 double‐perovskite films, leading to a large ferroelectric polarization (≈23.1 µC cm −2 ) and ultra‐enduring ferroelectric fatigue resistance exceeding 10 12 cycles without degradation. These results represent a significant enhancement in the performance boundaries of orthorhombic type‐II multiferroics. The ferroelectric switching dynamics reveal the intrinsic correlation between the continuous switchable ARNs and the outstanding ferroelectric behavior. These findings underscore the effectiveness of nanodomain‐coupling strategy for realizing high‐performance ferroelectrics and offer a promising pathway toward designing correlated oxide‐based ferroelectric semiconductor devices with exotic functionalities.