Efforts to combine the advantages of multiple systems to enhance functionlities through solid solution design present a great challenge due to the constraint imposed by the classical Vegard law. Here, we successfully navigate this trade off by leveraging the synergistic effect of chemical doping and strain engineering in solid solution system of BiFeO3 BaTiO3. Unlike bulks, a significant deviation from the Vegard law accompanying with enhanced multiferroism is observed in the strained solid solution epitaxial films, where we achieve a pronounced tetragonality, enhanced saturated magnetization, substantial polarization, high ferroelectric Curie temperature, all while maintaining impressively low leakage current. These characteristics surpass the properties of their parent BiFeO3 and BaTiO3 films. Moreover, the superior ferroelectricity has never been reported in corresponding bulks. These findings underscore the potential of strained BiFeO3 BaTiO3 films as lead-free, room-temperature multiferroics.
@article{arxiv.2410.12252,
title = {Large Enhancement of Properties in Strained Lead-free Multiferroic Solid Solutions with Strong Deviation from Vegard's Law},
author = {Tao Wang and Mingjie Zou and Dehe Zhang and Yu-Chieh Ku and Yawen Zheng and Shen Pan and Zhongqi Ren and Zedong Xu and Haoliang Huang and Wei Luo and Yunlong Tang and Lang Chen and Cheng-En Liu and Chun-Fu Chang and Sujit Das and Laurent Bellaiche and Yurong Yang and Xiuliang Ma and Chang-Yang Kuo and Xingjun Liu and Zuhuang Chen},
journal= {arXiv preprint arXiv:2410.12252},
year = {2024}
}