Ferroelectricity in layered bismuth oxide down to 1 nanometer

• 成果类型: Article
• 署名作者: Yang, Qianqian; Hu, Jingcong; Fang, Yue-Wen; Jia, Yueyang; Yang, Rui; Deng, Shiqing; Lu, Yue; Dieguez, Oswaldo; Fan, Longlong; Zheng, Dongxing; Zhang, Xixiang; Dong, Yongqi; Luo, Zhenlin; Wang, Zhen; Wang, Huanhua; Sui, Manling; Xing, Xianran; Chen, Jun; Tian, Jianjun; Zhang, Linxing
• 署名单位: University of Science & Technology Beijing; Beijing University of Technology; University of Basque Country; University of Basque Country; Shanghai Jiao Tong University; Tel Aviv University; Chinese Academy of Sciences; Institute of High Energy Physics, CAS; University of Chinese Academy of Sciences, CAS; King Abdullah University of Science & Technology; Chinese Academy of Sciences; University of Science & Technology of China, CAS; University of Science & Technology Beijing; University of Science & Technology Beijing
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-13739
• DOI: 10.1126/science.abm5134
• 发表日期: 2023-03-24
• 页码: 1218-1224
• 关键词: room-temperature ferroelectricity; thin-films; 1st-principles; polarization; thickness; dependence

摘要

Atomic-scale ferroelectrics are of great interest for high-density electronics, particularly field-effect transistors, low-power logic, and nonvolatile memories. We devised a film with a layered structure of bismuth oxide that can stabilize the ferroelectric state down to 1 nanometer through samarium bondage. This film can be grown on a variety of substrates with a cost-effective chemical solution deposition. We observed a standard ferroelectric hysteresis loop down to a thickness of similar to 1 nanometer. The thin films with thicknesses that range from 1 to 4.56 nanometers possess a relatively large remanent polarization from 17 to 50 microcoulombs per square centimeter. We verified the structure with first-principles calculations, which also pointed to the material being a lone pair-driven ferroelectric material. The structure design of the ultrathin ferroelectric films has great potential for the manufacturing of atomicscale electronic devices.